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Mil-Std-882E Safety Analysis

System of Systems Hazard Analysis

In this full-length (38-minute) session, The Safety Artisan looks at System of Systems Hazard Analysis, or SoSHA, which is Task 209 in Mil-Std-882E. SoSHA analyses collections of systems, which are often put together to create a new capability, which is enabled by human brokering between the different systems. We explore the aim, description, and contracting requirements of this Task, and an extended example to illustrate SoSHA. (We refer to other lessons for special techniques for Human Factors analysis.)

This is the seven-minute demo version of the full 38-minute video.

System of Systems Hazard Analysis: Topics

  • System of Systems (SoS) HA Purpose;
  • Task Description (2 slides);
  • Documentation (2 slides);
  • Contracting (2 slides);
  • Example (7 slides); and
  • Summary.

Transcript: System of Systems Hazard Analysis

Click here for the Transcript

Introduction

Hello everyone and welcome to the Safety Artisan. I’m Simon and today we’re going to be talking about System of Systems Hazard Analysis – a bit of a mouthful that. What does it actually mean? Well, we shall see.

System of Systems Hazard Analysis

So, for Systems of Systems Hazard Analysis, we’re using task 209 as the description of what to do taken from a military standard, 882E. But to be honest, it doesn’t really matter whether you’re doing a military system or a civil system, whatever it might be – if you’ve got a system of systems, then this will help you to do it.

Topics for this Session

Looking at what we’ve got coming up.

So, we look at the purpose of system of systems – and by the way, if you’re wondering what that is what I’m talking about is when we take different things that we’ve developed elsewhere, e.g. platforms, electronic systems, whatever it might be, and we put them together. Usually, with humans gluing the system together somewhere, it must be said, to make it all tick and fit together. Then we want this collection of systems to do something new, to give us some new capability, that we didn’t have before. So, that’s what I’m talking about when I say a system of systems. I’ll show you an example – it’s the best way. So, we’ve got a couple of slides on task description, a couple of slides or documentation, and a couple of slides on contracting. Tasks 209 is a very short task, and therefore I’ve decided to go through an example.

So, we’ve got seven slides of an example of a system of systems, safety case, and safety case report that I wrote. And hopefully, that will illustrate far better than just reading out the description. And that will also give us some issues that can emerge with systems of systems and I’ll summarize those at the end.

SOSHA Purpose

So, let’s get on. I’m going to call it the SOSHA for short; Systems of Systems Hazard Analysis. The purpose of the SOSHA, task 209, is to document or perform and document the analysis of the system of systems and identify unique system of systems hazards. So, things we don’t get from each system in isolation. This task is going to produce special requirements to deal with these hazards, which otherwise would not exist. Because until we put the things together and start using them for something new – We’ve not done this before.

Task Description (T209) #1

Task description: As in all of these tasks, the contractor shall perform and document an analysis of the system of systems to identify hazards and mitigation requirements. A big part of this, as I said earlier, we tend to use people to glue these collections, these portfolios, of systems together and humans are fantastic at doing that. Not always the ideal way of doing it, but sometimes it’s the only way of doing it within the constraints that we’ve got. The human is very important. The human will receive inputs from one or more systems and initiate outputs within the analysis and in fact within the real world, to be honest, which is what we’re trying to analyse. That’s probably a better way of looking at it.

And we’ve got to provide traceability of all those hazards to – it says – architecture locations, interfaces, data and stakeholders associated with the hazard. This is particularly important because with a system of systems each system tends to come with its own set of stakeholders, its own physical location, its own interfaces, etc, etc. The issue of managing all of those extraneous things and getting the traceability, it goes up. It is multiplied with every system you’ve got. In fact, I would say it was the square of. The example we’ll see: we’ve got three systems being put together in a system of systems and, in effect, we had nine times the amount of work in that area, I would say. I think that’s a reasonable approximation.

Task Description (T209) #2

Part two of the task description: The contractor will assess the risk of each hazard and recommend mitigation measures to eliminate the hazards. Or, very often, we can’t eliminate the hazards to reduce the associated risks. Then, as always with this standard, it says we’re going to use tables one, two and three, which are the severity, probability and the risk matrix that comes with the standard. Unless, of course, we have created or tailored our own matrix. Which we very often should do but it isn’t often done – I’ll have to do a session on how to do tailoring a matrix.

Then the contractor has got to verify and validate the effectiveness of those recommended mitigation measures. Now, that’s a really good point and I often see that missed. People come up with control measures or mitigation measures but don’t always assess how effective they’re going to be. Sometimes you can’t so we just have to be conservative but it’s not always done as well as it could be.

Documentation (T209) #1

So, let’s move on. Documentation: So, whoever does the analysis- the standard assumes it’s a contractor – shall document the results to include: you’ve got to describe the system of systems, the physical and functional characteristics of the system of systems, which is very important. Capturing these things is not a given. It’s not easy when you’ve got one system, but when you’ve got multiple systems, some of which are being misused to do something they’ve never done before, perhaps, then you’ve got to take extra care.

Then basically it says when you get more detail of the individual systems you need to supply that when it becomes available. Again, that’s important. And not only if the contractor supplies it, who’s going to check it? Who’s going to verify it? Etc., etc.

Documentation (T209) #2

Slide two on documentation: We’ve got to describe the hazard analysis methods and techniques used, providing a description of each method and technique used, and the assumptions and the data used in support. This is important because I’ve seen lots of times where you get a hazard analysis’ results and you only get the results. It’s impossible to verify those results or validate them to say whether they’ve been done in the correct context. And it’s impossible to say whether the results are complete or whether they’re up to date or even whether they were analysing the correct system because often systems come in different versions. So, how do you know that the version being analysed was the version you’re actually going to use? Without that description, you don’t know. So, it’s important to contract for these things.

And then hazard analysis results. What contents and formats do you want? It’s important to say. Also, we’re going to be looking to put the key items, the leading particular’s, from the results. The top-level results are going to go into the hazard tracking system which is more commonly known as a hazard log or a risk register, whatever it might be. Might be an Excel spreadsheet, might be a very fancy database, but whatever it’s going to be you’re going to have to standardize your fields of what things mean. Otherwise, you’re going to have – the data is going to be a mess and a poor quality and not very usable. So, again, you’ve got a contract for these things upfront and make sure you make clear definitions and say what you want.

Contracting #1

Contracting; implicitly, we’ve been talking about contracting already, but this is what a standard says. So, the request for proposal or statement of work has got to include the following. Typically we have an RFP before we’ve got a contract, so we need to have worked out what we need really early in the program or project, which isn’t always done very well. To work out what you need the customer, the purchaser, has probably got to do some analysis of their own in order to work all this stuff out. And I know I say this every time with these tasks, but it is so important. You can’t just dump everything on the contractor and expect them to produce good results because often the contractor is hamstrung. If you haven’t done your homework to help them do their work, then you’re going to get poor results and it’s not their fault.

So, we’ve got to impose the requirement for the task if we want it or need it. We’ve got to identify the functional disciplines. So, which specialists are going to do this work? Because very often the safety team are generalists. They do not have specialist technical knowledge in some of these areas. Or maybe they are not human factor specialists. We need somebody in, some human factor specialists, some user representatives, people who understand how the system will be used in real life and what the real-world constraints are. We need those stakeholders involved – That’s very important. We’ve got to identify those architectures and systems which make up the SOS -very important. The concept of operations. SOS is very much about giving capability. So, it’s all about what are you going to do with the whole thing when you put it together? How’s all that going to work?

Contracting #2

Interesting one, E, which is unique, I think, to task 209, what are the locations of the different systems and how far apart are they? We might be dealing with systems where the distance between them is so great that transmission time becomes an issue for energy or communications. Let’s say you’re bouncing a signal from an aircraft or a drone around the world via a couple of satellites back to home base. There could be a significant lag in communications. So, we need to understand all of these things because they might give rise to hazards or reduce the effectiveness of controls.

Part F; what analysis, methods, techniques do you want to use? And any special data to be used? Again, with these collections of systems that becomes more difficult to specify and more important. And then do we have any specific hazard management requirements? For example, are we using standard definitions and risk matrix from a standard or have we got our own? That all needs to be communicated.

Example #1

So, that is the totality of the task. As you can see, there’s not much to Task 209, so I thought it would be much more helpful to use an example, an illustration, and as they used to say in children’s TV, “Here’s one I made earlier” because a few years ago I had to produce a safety case report. I was the safety case report writer, and there was a small team of us generating the evidence, doing the analysis for the safety case itself.

What we were asked to do is to assure the safety of a system and – in fact, it was two systems but I just treat it as one – of a system for guiding aircraft onto ships in bad weather. So, all of these things existed beforehand. The aircraft were already in service. The ships were already in service. Some of the systems were already in service, but we were putting them together in a new combination. So, we had to take into account human factors. That was very important. We’ll see why in just a moment.

The operating environment, which was quite demanding. So, the whole point is to get the aircraft safely back to the ships in bad weather. They could do it in good weather you could do it visually, but in bad weather, visual wasn’t going to cut it. So, the operating environment- we were being asked to operate in a much more difficult environment. So, that changed everything and drove everything.

We’ve got to consider operating procedures because, as we’re about to see, people are gluing the systems together. So, how do they make it work? And also got to think about maintenance and management. Although in actual fact, we didn’t really consider maintenance and management that much. As an ex-maintainer, this annoys me, but the truth is people are much more focused on getting their capability and service. Often, they think about support as an afterthought. We’ll talk about that one day.

Example #2

Here’s a little demonstration of our system of systems. Bottom right-hand corner, we’ve got the ship with lots of people on the ship. So, if the aircraft crashes into it that could be bad news, not just for the people in the aircraft, but for the people on the ship – big risks there!

We’ve got our radar mounted on the ship so the ship is supplying the radar with power and control and data, telling it where to point for example. Also, the ship might be inadvertently interfering with the radar. There are lots of other electronic systems on the ship. There are bits of the ship getting in the way of the radar, depending on where you’ve put it, and so on and so forth. So, the ship interacts with the radar, the radar interacts with the ship, radars producing radiation. Could that be doing anything to the ship systems?

And then the radar is being operated. Now, I think that symbol is meant to indicate a DJ, but we’ve got the DJ wearing headphones and we got a disk there but it looks like a radar scope to me. So, I’ve just hijacked that. That’s the radar operator who is going to talk to the pilot and give the pilot verbal commands to guide them safely back to the ship. So, that’s how the system works.

In an ideal world, the ship would use the radar and then talk electronically direct to the aircraft and guide it – maybe automatically? That would be a much more sensible setup. In fact, that’s often the way it’s done. But in this particular case, we had to produce a bit of a – I hesitate to call it a lash-up because it was a multi-million-dollar project, but it was a bit of a lash-up.

So, there is the human factors. We’ve got a radar operator doing quite a difficult job and a pilot doing a very difficult job trying to guide their aircraft back onto the ship in bad weather. How are they going to interact and perform? And then lastly, as I alluded to earlier, the aircraft and the ship do actually interact in a limited way. But of course, it’s a physical interaction, so you can actually hurt people and of course, if we get it wrong, the aircraft interacts with the surface of the ocean, which is very bad indeed for the aircraft. So, we’ve got to be careful there. So, there’s a little illustration of our system of systems.

Example #3

And – this is the top-level argument that we came up with – it’s in goal structuring notation. But don’t worry too much about that – We’ll have a session on how to do GSN another time.

So, our top goal, or claim if you like, is that our system of systems is adequately safe for the aircraft to locate and approach the ship. So, that’s a very basic, very simple statement, but of course, the devil is in the detail and all of that detail we call the context. So, surrounding that top goal or claim, we’ve got descriptions of the system, of the aircraft and the ship. We got a definition of what we mean by adequately safe and we’ve got safety targets and reporting requirements.

So, what supports the top goal? We’ve got a strategy and after a lot of consultation and designing the safety argument, we came up with a strategy where we said, “We are going to show that all elements of the system of systems are safe and all the interactions are safe”. To do that, we had to come up with a scope and some assumptions to underpin that as well to simplify things. Again, they sit in the context, we just keep the essence of the argument down the middle.

And then underneath, we’ve got four subgoals. We aim to show that each system equipment is safe to operate, so it’s ready to be operated safely. Then each one is safe in operation so it can be operated safely with real people, etc. And then we’ve got all system safety requirements are satisfied for the whole collection of stuff and then finally that all interactions are safe. So, if we can argue all four of those, we should have covered everything. Now, I suspect if I did this again today, I might do it slightly differently. Maybe a little bit more elegantly, but that’s not the point. The point is, we came up with this and it worked.

Example #4

So, I’m going to unpack each one very briefly, just to illustrate some points. First of all, each component system is safe to operate. Each of these systems, bar one, had all been purchased already, sometimes a long time ago. They all came with their own safety targets, their own risk matrices, etc, etc. So, we had to make sure that when an individual system said, “This is what we’ve got to achieve” that that was good enough for the overall system of systems. So, we had to make sure that each system met its own safety requirements and targets and that they were valid in context.

Now, you would think that double-checking existing systems would be a foregone conclusion. In reality, we discovered that the ship’s communication system and its combat data system were not as robust as assumed. We discovered some practical issues were reported by stakeholders and we also discovered some flaws in previous analysis that had been accepted a long time ago. Now, in the end, those problems didn’t change the price of fish, as we say. It didn’t make a difference to the overall system of systems.

The frailty of the ship’s comms got sorted out and we discovered it didn’t actually matter about the combat system. So, we just assumed that the data coming out of the combat system was garbage and it didn’t make any difference. However, we did upset a few stakeholders along the way. So beware, people don’t like discovering that a system that they thought was “tickety-boo” was not as good as they thought.

Example #5

The second goal was to show that the system of systems is safe in operation. So, we looked at the actual performance. We looked at test results of the radar and then also we were very fortunate that trials of the radar on the ship with aircraft were carried out and we were able to look at those trials reports. And once again, it emerged that the system in the real world wasn’t operating quite as intended, or quite as people had assumed that it would. It wasn’t performing as well. So, that was an issue. I can’t say any more about that but these things happen.

Also, a big part of the project was we included the human element. So, as I’ve said before, we had pilots and we had radar air traffic talk-down operators. So, we brought in some human factors specialists. They captured the procedures and tasks that the pilots and the radar operators had to perform. They captured them with what’s called a Hierarchical Task Analysis, they did some analysis of the tasks and what could go wrong. Then they created a model of what the humans were doing and ran it through a simulation several thousand times. So in that way, they did some performance modelling.

Now, they couldn’t give us an absolute figure on workload or anything like that but what they could do – fortunately, our new system was replacing an older system which was even more informally cobbled together than the one that we were we were bringing in. And so, the Human Factor specialists were able to compare human performance in the old system vs. human performance with the new system. Very fortunately, we were pleased to find out that the predicted performance was far better with the new system. The new system was much easier to operate for both the pilots and the talk-down radar operators. So, that was terrific.

Example #6

So, the third one; All system of systems safety requirements are satisfied. Now, this is a bit more nebulous, this goal, but what it really came down to was when you put things together, very often you get what’s called emergent behaviour. As in things start to happen that you didn’t expect or you didn’t predict based on the individual pieces. It’s the saying, two plus two equals five. You get more out of a system – you get synergy for good or ill out when you start putting different things together.

So, does the whole thing actually work? And broadly speaking, the answer was yes, it works very well. There were some issues, a good example the old radar that they used to use to talk the planes down was a search radar so the operator could see other traffic apart from the plane they were they were guiding in. Now, the operator being able to see other things is both good and bad because on the one hand gives them improved situational awareness so they can warn off traffic if it’s a collision situation develops. But also, it’s bad because it’s a distraction for the operator. So, it could have gone either way.

So, the new radar was specialized. It focused only on the aircraft being talked down. So, the operator was blind to other traffic. So that was great in terms of decreasing operator workload and ultimately pilot workload as well. But would this increase the collision risk with other traffic? And I’ll talk about that in the summary briefly.

Example #7

And then our final goal is to show that all interactions are safe between the guidance system, the aircraft and the ship. This was a non-trivial exercise because ships have large numbers of electronic systems and there’s a very involved process to go through to check that a new piece of kit doesn’t interfere with anything else or vice versa.

And also, of course, does the new electronic system/the new radar does the radiation effect ship? Because you’ve got weapons on the ship and some of those explosive devices that the weapons uses are electrically initiated. So, could the radiation set off an explosion? So, all of those things had to be checked. And that’s a very specialized area.

And then we’ve got, does the system interfere with the aircraft and the aircraft with the system? What about the integration of the ship and the aircraft and the aircraft to the ship? Yet another specialized area where there’s a particular way of doing things. And of course, the aircraft people want to protect the aircraft and the ship people want to protect the ship. So, getting those two to marry up is also another one of those non-trivial exercises I keep referring to but it all worked out in the end.

Summary

Points to note: When we’re doing system of systems – I’ve got five points here, you can probably work some more points out from what I’ve said for yourself – but we’re putting together disparate systems. They’re different systems. They’ve been procured by different organizations, possibly, to do different things. The stakeholders who bought them and care about them have got different aims and objectives. They’ve got different agendas to each other. So, getting everyone to play nicely in the zoo can be challenging. And even with somebody pulling it all together at the top to say “This has got to work. Get with the program, folks!” there’s still some friction.

Particularly, you end up with large numbers of stakeholders. For example, we would have regular safety meetings, but I don’t think we ever had two meetings in a row with exactly the same attendees because with a large group of people, people are always changing over and things move up. And that can be a challenge in itself. We need to include the human in the loop in systems of systems because typically that’s how we get them all to play together. We rely on human beings to do a lot of translation work and in effect. So, how do the systems cope?

A classic mistake really with systems design is to design a difficult-to-operate system and then just expect the operator to cope. That can be from things as seemingly trivial as amusement park rides – I did a lesson on learning lessons from an amusement park ride accident only a month or two ago and even there it was a very complex system for two operators, neither of whom had total authority over the system or to be honest, really had the full picture of what was going on. As a result, there were several dead bodies. So, how did the operators cope, and have we done enough to support them? That’s a big issue with a system of systems.

Thirdly, this is always true with safety analysis, but especially so with system of systems. The real-world performance is important. You can do all the analysis in the world making certain assumptions and the analysis can look fine, but in the real world, it’s not so simple. We have to do analysis that assumes the kit works as advertised because you’ve got nothing else to go on until you get the test results and you don’t get them until towards the end of the program. So, you’re going down a path, assuming that things work, that they do what they say on the tin, and perhaps you then discover they don’t do what they say on the tin. Or they don’t do everything they say on a tin. Or they do what they say and they do some other things that you weren’t expecting as well and then you’ve got to deal with those issues.

And then fourthly, somewhat related to what I’ve just talked about, but you put systems together in an informal way, perhaps, and then you discover how they actually get on – what really happens. In reality, once you get above a certain level of complexity, you’re not really going to discover all the emergent behaviours and consequences until you get things into service and it’s clocked up a bit of time in service under different conditions in the real world. In fact, that was the case with this and I think with a system of systems, you’ve just got to assume that it’s sufficiently complex that that is the case.

Now, that’s not an unsolvable problem but, of course, how do you contract for that? Where you’ve got your contractors wanting you to accept their kit and pay them at a certain date or a certain point in the program, but you’re not going to find out whether it all truly works until it’s got into service and been in service for a while. So, how do you incentivize the contractor to do a good job or indeed to correct defects in a timely manner? That’s quite a challenge for system systems and it’s something that needs thinking about upfront.

And then finally, I’ve said, remember the bigger picture. It’s very easy when you’re doing analysis and you’ve made certain assumptions and you set the scope, it’s very easy to get fixated on that scope and on those assumptions and forget the real world is out there and is unpredictable. We had lots of examples of that on this program. We had the ship’s comms that didn’t always work properly, we couldn’t rely on the combat system, the radar in the real world didn’t operate as well as it said in the spec, etc, etc. There were lots of these things.

And, one example I mentioned was that with the new radar, the radar operator does not see any traffic other than the aircraft that is being guided in. So, there’s a loss of situational awareness there and there’s a risk, maybe an increased risk, of collision with other traffic. And that actually led to a disagreement in our team because some people who had got quite fixated on the analysis and didn’t like the suggestion that maybe they’d missed something. Although it was never put in those terms, that’s the way they took it. So, we need to be careful of egos. We might think we’ve done a fantastic analysis and we’ve produced hundreds of pages of data and fault trees or whatever it might be but that doesn’t mean that our analysis has captured everything or that it’s completely captured what goes on in the real world because that’s very difficult to do with such a complex system of systems.

So, we need to be aware of the bigger picture, even if it’s only just qualitatively. Somebody, a little voice, piping up somewhere saying, “What about this? And we thought about that? I know we’re ignoring this because we’ve been told to but is that the right thing to do?” And sometimes it’s good to be reminded of those things and we need to remember the big picture.

Copyright Statement

Anyway, I’ve talked for long enough. It just remains for me to point out that all the text in quotations, in italics, is from the military standard, which is copyright free but this presentation is copyright of the Safety Artisan. As I’m recording this, it’s the 5th of September 2020.

For More …

And so if you want more, please do subscribe to the Safety Artisan channel on YouTube and you can see the link there, but just search for Safety Artisan in YouTube and you’ll find us. So, subscribe there to get free video lessons and also free previews of paid content. And then for all lessons, both paid and free, and other resources on safety topics please visit the Safety Artisan at www.safetyartisan.com/  where I hope you’ll find much more good stuff that you find helpful and enjoyable.

End: System of Systems Hazard Analysis

So, that is the end of the presentation and it just remains for me to say thanks very much for watching and listening. It’s been good to spend some time with you and I look forward to talking to you next time about environmental analysis, which is Task 210 in the military standard. That’ll be next month, but until then, goodbye.

Categories
Mil-Std-882E Safety Analysis

Health Hazard Analysis

In this full-length (55-minute) session, The Safety Artisan looks at Health Hazard Analysis, or HHA, which is Task 207 in Mil-Std-882E. We explore the aim, description, and contracting requirements of this complex Task, which covers: physical, chemical & biological hazards; Hazardous Materials (HAZMAT); ergonomics, aka Human Factors; the Operational Environment; and non/ionizing radiation. We outline how to implement Task 207 in compliance with Australian WHS. (We refer to other lessons for specific tools and techniques, such as Human Factors analysis methods.)

This is the seven-minute-long demo. The full version is a 55-minute-long whopper!

Health Hazard Analysis: Topics

  • Task 207 Purpose;
  • Task Description;
  • ‘A Health Hazard is…’;
  • ‘HHA Shall provide Information…’;
  • HAZMAT;
  • Ergonomics;
  • Operating Environment;
  • Radiation; and
  • Commentary.

Health Hazard Analysis: Transcript

Click here for the Transcript

Introduction

Hello, everyone, and welcome to the Safety Artisan. I’m Simon, your host, and today we are going to be talking about health hazard analysis.

Task 207: Health Hazard Analysis

This is task 207 in the Mil. standard, 882E approach, which is targeted for defense systems, but you will see it used elsewhere. The principles that we’re going to talk about today are widely applicable. So, you could use this standard for other things if you wish.

Topics for this Session

We’ve got a big session today so I’m going to plough straight on. We’re going to cover the purpose of the task; the description; the task helpfully defines what a health hazard is; says what health hazard analysis, or HHA, shall provide in terms of information. We talk about three specialist subjects: Hazardous materials or hazmat, ergonomics, and operating environment. Also, radiation is covered, another specialist area. Then we’ll have some commentary from myself.

Now the requirements of the standard of this task are so extensive that for the first time I won’t be quoting all of them, word for word. I’ve actually had to chop out some material, but I’ll explain that when we come to it. We can work with that but it is quite a demanding task, as we’ll see.

Task Purpose

Let’s look at the task purpose. We are to perform and document a health hazard analysis and to identify human health hazards and evaluate what it says, materials and processes using materials, etc, that might cause harm to people, and to propose measures to eliminate the hazards or reduce the associated risks. In many respects, it’s a standard 882 type approach. We’re going to do all the usual things. However, as we shall see it, we’re going to do quite a lot more on this one.

Task Description #1

So, task description. We need to evaluate the potential effects resulting from exposure to hazards, and this is something I will come back to again and again. It’s very easy dealing in this area, particularly with hazardous materials, to get hung up on every little tiny amount of potentially hazardous material that is in the system or in a particular environment and I’ve seen this done to death so many times. I’ve seen it overdone in the UK when COSHH, a control of substance hazardous to health, came in in the military. We went bonkers about this. We did risk assessments up the ying-yang for stuff that we just did not need to worry about. Stuff that was in every office up and down the land. So, we need to be sensible about doing this, and I’ll keep coming back to that.

So, we need to do as it says; identification assessment, characterisation, control, and communicate assets in the workplace environment. And we need to follow a systems approach, considering “What’s the total impact of all these potential stressors on the human operator or maintainer?” Again, I come from a maintenance background. The operator often gets lots of attention because a) because if the operator stuffs up, you very often end up with a very nasty accident where lots of people get hurt. So, that’s a legitimate focus for a human operator of a system.

But also, a lot of organizations, the executive management tend to be operators because that’s how the organization evolves. So, sometimes you can have an emphasis on operations and maintenance and support, and other things get ignored because they’re not sexy enough to the senior management. That’s a bad reason for not looking at stuff. We need to think about the big picture, not just the people who are in control.

Task Description #2

Moving on with task description. We need to do all of this good stuff and we’re thinking about materials and components and so forth, and if they cause or contribute to adverse effects in organisms or offspring. We’re talking about genetic effects as well. Or pose a substantial present or future danger to the environment. So in 882, we are talking about environmental impact as well as human health impact. There is a there is an environmental task as well that is explicitly so.

Personally, I would tend to keep the human impact and the environmental impact separate because there are very often different laws that apply to the two. If you try and mix them together or do a sort of one size fits all analysis, you’ll frequently make life more difficult for yourself than you need to. So, I would tend to keep them separate. However, that’s not quite how the standard is written.

A Health Hazard is …

So what is a health hazard? As it says, a health hazard is a condition and it’s got to be inherent to the operation, etc, through to disposal of the system. So, it’s cradle to grave – That’s important. That’s consistent with a lot of Western law. It’s got to be capable of causing death, injury, illness, disability, or even in this standard, they’ve just reduced the job performance of personnel by exposure to physiological stresses.

Now I’m getting ahead of myself because, in Australia, health hazards can include psychological impacts as well, not just impacts on physical health. Now reduced job performance? – Are we really interested in minor stuff? Maybe not. Maybe we need to define what we mean by that. Particularly when it comes to operators or maintainers making mistakes, perhaps through fatigue that can have very serious consequences.

So, this analysis task is going to address lots of causes or factors that we typically find in big accidents and relate them to effects on human performance. Then it goes on to specify that certain specific hazards must be included chemical, physical, biological, ergonomic – for ergonomic, I would say human factors, because when you look at the standard, what we call ergonomics is much wider than the narrow definition of ergonomics that I’m used to.

Now, this is the first area that chops some material because where in a-d it says e.g. in those examples there is in effect a checklist of chemical, physical, biological, and ergonomic hazards that you need to look at. This task has its own checklist. You might recall when we talked about preliminary hazard identification, a hazard checklist is a very good method for getting broad coverage in general. Now, in this task, we have further checklists that are specific to human health. That’s something to note.

We’ve also got to think about hazardous materials that may be formed by test, operation, maintenance, disposal, or recycling. That’s very important, we’ll come back to that later. Thinking about crashworthiness and survivability issues. We’ve got to also think about it says non-ionizing radiation hazards, but in reality, we’ve got to consider ionizing as well. If we have any radioactive elements in our system and it does say that in G. So, we’ve got to do both non-ionizing and ionizing.

HHA Shall Provide Info #1

What categories of information should this health hazard analysis generate? Well, first of all, it’s got to identify hazards and as I’ve said or hinted at before, we’ve got to think about how could human beings be exposed? What is the pathway, or the conditions, or mode of operations by which a hazardous agent could come into contact with a person? I will focus on people. So, just because there is a potentially hazardous chemical present doesn’t mean that someone’s going to get hurt. I suspect if I looked around in the computer in front of me that I’m recording this on or at the objects on my desk, there are lots of materials that if I was to eat them or swallow them or ingest them in some other way would probably not do me a lot of good. But it’s highly unlikely that I’m going to start eating them so maybe we don’t need to worry about that.

HHA Shall Provide Info #2

We also need to think about the characterization of the exposure. Describing the assessment process: names of the tools or any models used; how did we estimate intensities of energy or substances at the concentrations and so on and so forth? This is one of those analyses that are particularly sensitive to the way we go about doing stuff. Indeed, in lots of jurisdictions, you will be directed as to how you should do some of these analyses and we’ll talk about that in the commentary later. So, we’ve got to include that. We’ve got to “show our working” as our teachers used to tell us when preparing us for exams.

HHA Shall Provide Info #3

We’ve got to think about severity and probability. Here the task directs us to use the standard definition tables that are found in 882. I talked about those under task 202 so I’m not going to talk about further here. Now, of course, we can, and maybe should tailor these matrices. Again, I’ve talked about that elsewhere, but if we’re not using the standard matrices and tables, then we should set out what we’ve done and why that’s appropriate as well.

HHA Shall Provide Info #4

Then finally, the mitigation strategy. We shouldn’t be doing analysis for the sake of analysis. We should be doing to say, “How can we make things better?” And in particular for health, “How can we make things acceptable?” Because health hazards very often attract absolute limits on exposure. So, questions of SFARP or ALARP or cost-benefit analysis simply may not enter into the equation. We simply may be direct to say “This is the upper limit of what you can expose a human being to. This is not negotiable.” So, that’s another important difference with this task.

Three More Topics

Now, at this point, I am just foreshadowing. We’re about to move on to talk about some different topics. First of all, in this section, we’re going to talk about three particular topics. Hazardous material or HAZMAT for short; ergonomics; and the operational environment. When we say the operational environment, it’s mainly about the people, aspects of the system, and the environment that they experience. Then after these three, we would go on to talk about radiation. There are special requirements in these three areas for HAZMAT, ergonomics, and operational environment.

HAZMAT (T207) #1

First of all, we have to deal with HAZMAT. If it’s going to appear in our system, or in the support system, we’ve got to identify the HAZMAT and characterize it. There are lots of international and national standards about how this is to be done. There’s a UN convention on hazardous materials, which most countries follow. And then there will usually be national standards as well that direct what we shall do. More on that later. So, we’ve got to think about the HAZMAT.

A word of caution on that. Certainly in Australian defence, we do HAZMAT to death because of a recent historical example of a big national scandal about people being exposed to hazardous materials while doing defence work. So, the Australian Defence Department is ultrasensitive about HAZMAT and will almost certainly mandate very onerous requirements on performing this. And whilst we might look at that go “This is nuts! This is totally over the top!” Unfortunately, we just have to get on with it because no one is going to make, I’m afraid, a sensible decision about the level of risk that we don’t have to worry about because it’s just too sensitive a topic.

So, this is one of those areas were learning from experience has actually gone a bit wrong and we now find ourselves doing far too much work looking at tiny risks. Possibly at the expense of looking at the big picture. That’s just something to bear in mind.

HAZMAT (T207) #2

So, lots of requirements for HAZMAT. In particular, we need to think about what are we going to do with it when it comes to disposal? Either disposal of consumables, worn components or final disposal of the system. And very often, the hazardous material may have become more hazardous. In that, let’s say engine or lubricating oil will probably have metal fragments in it once it’s been used and other chemical contamination, which may render it carcinogenic. So, very often we start with a material that is relatively harmless, but use – particularly over a long period of time – can alter those chemicals or introduce contaminants and make them more dangerous. So, we need to think about the full life of the system.

Ergonomics (T207) #1

Moving on to ergonomics, and this is another big topic. Now, Mil.standard 882 doesn’t address human factors, in my view, particularly well. The human factors stuff gets buried in various tasks and we don’t identify a separate human factors program with all of the interconnections that you need in order to make it fully effective. But this is one task where human factors do come in, very much so, but they are called ergonomics rather than human factors. Under this task description, we need to think about mission scenarios. We need to think about the staff who will be exposed as operators or maintainers, whatever they might be doing. We’ve got to start to characterize the population at risk.

Ergonomics (T207) #2

We’ve got to think about the physical properties of things that personnel will handle or wear and the implications that has on body weight. So, for example, there is a saying that the “Air Force and the Navy man their equipment and the army equip their men”. Apologies for the gendered language but that’s the saying. So, we’re putting human beings – very often – inside ships and planes and tanks and trucks. And we’re also asking soldiers to carry – very often – lots of heavy equipment. Their rations, their weapons, their ammunition, water, various tools and stuff that they need to survive and fight on the battlefield. And all that stuff weighs and all of that stuff, if you’re running about carrying it, bangs into the body and can hurt people. So, we need to address that stuff.

Secondly, we need to look at physical and cognitive actions that operators will take. So, this is really very broad once we get into the cognitive arena thinking about what are the operators going to be doing. And exposures to mechanical stress while performing work. So, maybe more of a focus on the maintainer in part three. Now, for all of this stuff, we need to identify characteristics of the design of the system or the design of the work that could degrade performance or increase the likelihood of erroneous action that could result in mishaps or accidents.

This is classic human factor’s stuff. How might the designed work or the designed equipment induce human error? So, that’s a huge area of study for a lot of systems and very important. And this will be typically a very large contributor to serious accidents and, in fact, accidents of all kinds. So, it should be an area of great focus. Often it is not. We just tend to focus on the so-called technical risks and overdo that while ignoring the human in the system. Or just assuming that the human will cope, which is worse.

Ergonomics (T207) #3

Continuing with ergonomics. How many staff do we need to operate and maintain the system and what demands are we placing on them? Also, if we overdo these demands, what are we going to do about that? Now, this can be a big problem in certain systems. I come from an aviation background and fatigue and crew duty time tend to be very heavily policed in aviation. But I was actually quite shocked when I sort of began looking at naval surface ships, submarines, where it seemed that fatigue and crew duty time was not well policed. In fact, there even seemed to be, in some places, quite a macho attitude to forcing the crew into working long hours. I say macho attitude because the feeling seemed to be “Well if you can’t take it, you shouldn’t have joined.”

So, it seems to be to me, quite a negative culture in those areas potentially, and it’s something that we need to think about. In particular, I’ve noticed on certain projects that you have a large crew who seem to be doing an extraordinary amount of work and becoming very fatigued. That’s concerning because, of course, you could end up with a level of fatigue where the crew might as well – they’re making mistakes to the same level as a drunk driver. So, this is something that needs to be considered carefully and given the attention it deserves.

Operating Environment #1

Moving on to the operating environment. How will these systems be used and maintained? And what does that imply for human exposure? This is another opportunity where we need to learn from legacy systems and go back and look at historical material and say “What are people being exposed to in the past? And what could happen again?”

Now, that’s important. It’s often not very systematically done. We might go and talk to a few old, bold operators and maintainers and ask their advice on the things that can go wrong but we don’t always do it very systematically. We don’t always survey past hazard and accident data in order to learn from it. Or if we do there is sometimes a tendency to say, “That happened in the past, but we will never make those mistakes. We’re far too clever to stuff up like that – like our predecessors did.” Forgetting that our predecessors were just as clever as we are and just as well –meaning as we are but they were human and so are we.

I think pride can get in the way of a lot of these analyses as well. And there may be occasions where we’re getting close to exposure limits, where regulations say we simply cannot expose people to a certain level of noise, or whatever, and then “How are we going to deal with that? How are we going to prevent people from being overexposed?” Again, this can be a problem area.

Operating Environment #2

This next bit of operating environment is really – I said about putting people in the equipment. Well, this is this bit. This is part A and B. So, we’re thinking about “If we stick people in a vehicle – whether it be a land vehicle, marine vehicle, an air vehicle, whatever it might be – what is that vehicle going to do to their bodies?” In terms of noise, of vibration and stresses like G forces, for example, and shock, shock loading? Could we expose them to blast overpressure or some other sudden changes of pressure or noise that’s going to damage their ears, temporarily or permanently? Again, remarkably easy to do. So, that’s that aspect.

Operating Environment #3

Moving on, we continue to talk about noise and vibration in general. In this particular standard, we’ve got some quite stringent guidance on what needs to be looked at. Now, these requirements, of course, are assuming a particular way of doing things, which we will come to later. There are a lot of standards reference by task 207. This task is assuming that we’re going to do things the American government or the American military way, which may not be appropriate for what we’re doing or the jurisdiction we’re in. So, we’ll just move on.

Operating Environment #4

Then again, talking about noise, blast, vibration, how are we going to do it? Some quite specific requirements in here. And again, you’ll notice, two-thirds of the way down in the paragraph, I’ve had to chop out some examples. There is some more in effect, hazard checklists in here saying we must consider X, Y, Z. Now, again, this seems to be requiring a particular way of doing things that may not be appropriate in a non-American defence environment.

However, the principle I think, to take away from this is that this is a very demanding task. If we consider human health effects properly, it’s going to require a lot of work by some very specialist and skilled people. In fact, we may even get in some specialist medical people. If you work in aviation or medicine, you may be aware that there is a specialist branch of medicine for called aviation medicine where these things are specifically considered. And similarly, there are medical specialists are a diving operations and other things where we expose human beings to strange effects. So, this can be a very, very demanding task to follow.

Operating Environment #5

So, when we’re going to equip people with protective equipment or we’re going to make engineering changes to the system to protect them, how effective are these things going to be? And given that most of these things have a finite effectiveness – they’re rarely perfect unless you can take the human out of the system entirely, then we’re going to be exposing people to some level of hazard and there will be some risk that that might cause that injury.

So, how many individuals are we going to expose per platform or over the total population exposed over the life of the system? Now, bearing in mind we’re talking sometimes about very large military systems that are in service for decades. This can be thousands and thousands of people. So, we may need to think about that and certainly in Australia, if we expose people to certain potential contaminants and noise, we may have to run a monitoring program to monitor the health and exposure of some of this exposed population or all of them. So, that can be a major task and we would need to identify the requirements to do that quite early on, hopefully.

And then, of course, again, we’re not doing this for the sake of it. How can we optimize the design and effectively reduce noise exposure and vibration exposure to humans? And how did we calculate it? How did we come to those conclusions? Because we’re going to have to keep those records for a long, long time. So, again, very demanding recording requirements for this task.

Operating Environment #6

And then I think this is the final one on operating environment. What are the limitations of this protective equipment and what burden do they impose? Because, of course, if we load people up with protective equipment that may introduce further hazards. Maybe we’re making the individual more likely to suffer a muscular musculoskeletal disorder.

Or maybe we are making them less agile or reducing their sensitivity to noise? Maybe if we give people hearing protection, if somebody else has assumed that they will hear a hazard coming, well, they’re not going to anymore, are they? If they’re wearing lots of protective equipment, they may not be as aware of the environment around them as they once were. So, we can introduce secondary hazards with some of this stuff. And then we need to look at the trade-offs. When and where? Is it better to equip people or not to equip people and limit their exposure or just keep them away altogether?

Radiation (T207)

So moving on briefly, we’re just going to talk about radiation. Now in this task – again, I’ve had to chop a lot of stuff out – you’ll see that in square brackets this task refers to certain US standards for radiation. Both ionizing and non-ionizing, lasers and so forth. That’s appropriate for the original domain, which this standard was targeted at. It may be wholly inappropriate for what you and I are doing.

So, we need to look at the principles of this task, but we may need to tailor the task substantially in order to make it appropriate for the jurisdiction we’re working in. Again, we’re going to have to keep these records for a long time. Radiation is always going to be dreaded by humans so it’s a controversial topic. We’re going to have to monitor people’s exposure and protect them and show that we have done so, potentially decades into the future. So, we should be looking for the very highest standards of documentation and recording in these areas because they will come under scrutiny.

Contracting #1

Moving onto contracting, this is more of a standard part of this task or part of the standard, I should say. These words or very similar words exist in every task. So, I’m not going to go through all of these things in any great detail. It’s worth noting, and I’ll come back to this in part B, we may need to direct whoever is doing the analyses to consider or exclude certain areas because it’s quite possible to fritter away a lot of resources doing either a wide but shallow analysis that fails to get to the things that can really hurt people.

So, we might be doing a superficial analysis or we might go overboard on a particular area and I’ve mentioned HAZMAT but there are many things that people can get overexcited about. So, we might see people spending a lot of time and effort and money in a particular area and ignoring others that can still hurt people. Even though they might be mundane, not as sexy. Maybe the analysts don’t understand them or don’t want to know. So, the customer who is paying for this may need to direct the analysis. I will come on to how you do that later.

Also the customer or client may need to specify certain sources of information, certain standards, certain exposure standards, certain assumptions, certain historical sets of data and statistics to be used. Or some statistics about the population, because, of course, for example, the military systems, the people who operate military systems tend to be quite a narrow subset of the population. So, there are very often age limits. Frontline infantry soldiers tend to be young and fit. In certain professions, you may not be allowed to work if you are colour-blind or have certain disabilities. So, it may be that a broad analysis of the general population is not appropriate for certain tasks.

It may be perfectly reasonable to assume certain things about the target population. So, we need to think about all of these things and ensure that we don’t have an unfocused analysis that as a result is ineffective or wastes a lot of money looking at things that don’t really matter, that are irrelevant.

Contracting #2

Standards and criteria. In part F, there are 29 references which the standard lists, which are all US military standards or US legal standards. Now, probably a lot of those will be inappropriate for a lot of jurisdictions and a lot of applications. So, there’s going to be quite a lot of work there to identify what are the appropriate and mandatory references and standards to use. And as I said, in the health hazard area, there are often a lot. So, we will often be quite tightly constrained on what to do.

And Part H, if the customer knows or has some idea of the staff numbers and profile, they’re going to be exposed to this system of operating and maintaining the system. That’s a very useful information and needs to be shared. We don’t want to make the analyst, the contractor, guess. We want them to use appropriate information. So, tell them and make sure you’ve done your homework, that you tell them the right thing to do.

Commentary #1

So, that’s all of the standard. I’ve got four slides now of commentary. And the first one, I just want to really summarize what we’ve talked about and think about the complexity of what we’re being asked to do. First bullet point, we are considering cradle to grave operation and maintenance and disposal. Everything associated with, potentially, quite a complex system. Now, this lines up very nicely with the requirements of Australian law, which require us to do all of this stuff. So, it’s got to be comprehensive.

Second bullet point, we’ve got to think about a lot of things. Death and injury, illness, disability, the effects on and could we infect somebody or contaminate somebody with something that will cause birth defects in their offspring? There’s a wide range of potential vectors of harm that we’re talking about here, and we will probably – for some systems, we will need to bring in some very specialist knowledge in order to do this effectively. And also thinking about reduced job performance – this is one aspect of human factors. This task is going to linking very strongly to whatever human factors program we might.

Thirdly, we’ve got to think about chemical, physical, and biological hazards. So, again, there’s a wide range of stuff to think about there. An example of that is hazmat and the requirements on hazmat are, in most jurisdictions, tend to be very stringent. So, that is going to be done and we need to be prepared to do a thorough job and demonstrate that we’ve done a thorough job and provide all the evidence.

Then we’ve also got ergonomics. Actually, strictly speaking, we’re talking human factors here because it’s a much wider definition than what the definition of ergonomics that I’m used to, which tends to be purely physical effects on a human. Because we’re talking about cognitive and perception and job performance as well and also we’ve got vibration and acoustics. So, again, particular medical effects and stringent requirements. So, a whole heap of other specialists work there.

And operating environment, thinking about the humans that will be exposed. How are we going to manage that? What do we need to specify in order to set up whatever medical monitoring program of the workforce we might have to bring in in the future through life? So, again, potentially a very big, expensive program. We need to plan that properly.

Then finally, radiation. Another controversial topic which gets lots of attention. Very stringent requirements, both in terms of exposure levels and indeed we will often be directed as to how we are to calculate and estimate stuff. It’s another specialist area and it has to be done properly and thoroughly.

Overall, every one of those seven bullet points shows how complex and how comprehensive a good health hazard analysis needs to be. So, to specify this well, to understand what is required and what is needed through life, for the program to meet our legal and regulatory obligations, this is a big task and it needs a lot of attention and potentially a lot of different specialist knowledge to make it work. I flogged that one to death, so I’ll move on.

Commentary #2

Now, as I’ve said before, too, this is an American military standard, so it’s been written to conform to that world. Now in Australia, the requirements of Australian work, health and safety are quite different to the American way of doing things. Whilst we tend to buy a lot of American equipment and there’s a lot of American-style thinking in our military and in our defence industry, actually, Australian law much is much more closely linked to English law. It’s a different legal basis to what the Americans do. So Australian practitioners take note.

It’s very easy to go down the path of following this standard and doing something that will not really meet Australian requirements. It’ll be, “We’ll do some work” and it may be very good work, but when we come to the end and we have to demonstrate compliance with Australian requirements, if we haven’t thought about and explicitly upfront, we’re probably in for a nasty shock and a lot of expensive rework that will delay the program. And that means we’re going to become very, very unpopular very quickly. So, that’s one to avoid in my experience.

So, we will need to tailor task 207 requirements upfront in order to achieve WHS compliance. And the client customer needs to do that and understand that not the – well the contractor needs to. The analysts need to understand that. But the customer needs to understand that first, otherwise, it won’t happen.

Commentary #3

Let’s talk a bit more about tailoring for WHS. For example, there are several WHS codes of practice which are relevant. And just to let you know, these codes of practice cover not only requirements of what you have to achieve, but also, to a degree, how you are to achieve them. So, they mandate certain approaches. They mandate certain exposure standards. Some of them also list a lot of other standards that are not mandated but are useful and informative.

So, we’ve got codes of practice on hazardous manual tasks so avoiding muscular-skeletal injuries. We’ve got several codes of practice on hazardous chemicals. So, we’ve got a COP specifically on risk management and risk assessment of hazardous chemicals, on safety data sheets, on labelling of HAZCHEM in a workplace. We’ve got a COP on noise and hearing loss and also, we have other COPs on specific risks, such as asbestos, electricity and others, depending on what you’re doing. So, potentially there is a lot of regulation and codes of practice that we need to follow.

And remember that COPs are, while they contain regulations, they also are a standard that a court will look to enforce if you get prosecuted. If you wind up in court, the prosecution will be asking questions to determine whether you’ve met the requirements of COP or not. If you can’t demonstrate that you’ve met them, you might have done a whole heap of work and you might be the greatest expert in the world on a certain kind of risk, but if he can’t demonstrate that you’ve met at minimum the requirements of COP – because they are minimum requirements – then you’re going to be in trouble. So, you need to be aware of what those things are.

Then on radiation, we have separate laws outside the WHS. So, we have the Australian Radiation Protection and Nuclear Safety Agency, ARPANSA, and there is an associated act and associated regulations and some COP as well. So, for radiation side, there’s a whole other world that you’ve got to be aware of and associated with all of this stuff are exposure standards.

Commentary #4

Finally, how do we do all of this without spending every dollar in the defence budget and taking 100 years to do it? Well, first of all, we need to set our scope and priorities. So, before we get to Task 207, the client/the customer should be involving end-users and doing a preliminary hazard identification exercise. That should be broad and as thorough as possible. They should also be doing a preliminary hazardous hazard analysis exercise, Task 202, to think about those hazards and risks further.

Also, you should be doing Task 203, which is system requirements hazard analysis. We need to be thinking about what are the applicable requirements for my system from the law all the way down to what specific standards? What codes of practice? What historical norms do we expect for this type of equipment? Maybe there is industry good practice on the way things are done. Maybe as we work through the specifications for the equipment, we will derive further requirements for hazard controls or a safety management system or whatever it might be. That’s a big job in itself.

So, we need to do all three of those tasks, 201, 202, 203, in order to be prepared and ready to focus on those things that we think might hurt us. Might hurt people physically, but also might hurt us in terms of the amount of effort we’re going to have to make in order to demonstrate compliance and assurance. So, that will focus our efforts.

Secondly, when we need to do the specialist analyses and we may not always need to do so. This is where 201, 202, and 203 come in. But where we need to do specialist analyses, we may need to find specialist staff who are competent to do these this kind of unusual or specialist work and do it well. Now, typically, these people are not cheap, and they tend to be in short supply. So, if you can think about this early and engage people early, then you’re going to get better support.

You’re probably going to get a better deal because in my experience if you call in the experts and ask their opinion early on, they’re more likely to come back and help you later. As opposed to, if you ignore them or disregard their advice and then ask them for help because you’re in trouble, they may just ignore you because they’ve got so much work on. They don’t need your work. They don’t need you as a client. You may find yourself high and dry without the specialists you need or you may find yourself paying through the nose to get them because you’re not a priority in their eyes. So do think about this stuff early, I would suggest and do cultivate the specialist. If you get them in early and listen to them and they feel involved, you’re much more likely to get a good service out of them.

So thirdly, try not to do huge amounts of work on stuff that doesn’t really have a credible impact on health. Now, I know that sounds like a statement of the blinking obvious, but because people get so het up about health issues, particularly things like radiation and other hazards that humans can’t see: we dread them. We get very emotional about this stuff and therefore, management tends to get very, very worried about this stuff. And I’ve seen lots of programs spend literally millions of dollars analyzing stuff to death, which really doesn’t make any difference to the safety of people in the real world. Now, obviously, that’s wasted money, but also it diverts attention from those areas that really are going to cause or could cause harm to people through the life of the system.

So, we need to use that risk matrix to understand what is the real level of risk exposure to human beings and therefore, how much money should we be spending? How much effort and priority should we be spending on analyzing this stuff? If the risk is genuinely very low, then probably we just take some standard precautions, follow industry best practice, and leave it at that and we keep our pennies for where they can really make a difference.

Now, having said that, there are some exceptions. We do need to think about accident survivability. So, what stresses are people going to be exposed to if their vehicle is an accident? How do we protect them? How do they escape afterward? Hopefully. How do we get them to safety and treat the injured? And so on and so forth. That may be a very significant thing for your system.

Also post-accident scenarios in terms of – very often a lot of hazardous materials are safely locked away inside components and systems but if the system catches fire or is smashed to pieces and then catches fire, then potentially a lot of that HAZMAT is going to become exposed. Very often materials that pose a very low level of risk, if you set them on fire and then you look at the toxic residue left behind after the fire, it becomes far more serious. So, that is something to consider. What do we do after we’ve had an accident and we need to sort of clean up the site afterward? And so on and so forth.

Again, this tends to be a very specialist job so maybe we need to get in some specialists to give us advice on that. Or we need to look to some standards if it’s a commonplace thing in our industry, as it often is. We learn we learned from bitter experience. Well, hopefully, we learn from bitter experience.

Copyright Statement

So, that’s it from me. I appreciate it’s been a long session, but this is a very complex task and I’ve really only skimmed the surface on this and pointed you at sort of further reading and maybe some principles to look at in more depth. So, all the quotations are from the Mill standard, which is copyright free. But this presentation is copyright of the Safety Artisan.

For More…

And for more information on this topic and others, and for more resources, do please visit www.safetyartisan.com. There are lots of free resources on the website as well, and there’s plenty of free videos to look at.

End: Health Hazard Analysis

So, that is the end of the session. Thank you very much for listening. And all that remains for me to say is thanks very much for supporting the work of the Safety Artisan and tuning into this video. And I wish you every success in your work now and in the future. Goodbye.

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Mil-Std-882E Safety Analysis

Operating & Support Hazard Analysis

In this full-length session, The Safety Artisan looks at Operating & Support Hazard Analysis, or O&SHA, which is Task 206 in Mil-Std-882E. We explore Task 206’s aim, description, scope, and contracting requirements. We also provide value-adding commentary, which explains O&SHA: how to use it with other tasks; how to apply it effectively on different products; and some of the pitfalls to avoid. We refer to other lessons for specific tools and techniques, such as Human Factors analysis methods.

This is the seven-minute-long demo. The full version is about 35 minutes long.

Operating & Support Hazard Analysis: Topics

  • Task 206 Purpose:
    • To identify and assess hazards introduced by O&S activities and procedures;
    • To evaluate the adequacy of O&S procedures, facilities, processes, and equipment used to mitigate risks associated with identified hazards.
  • Task Description (six slides);
  • Reporting (two slides);
  • Contracting (two slides); and
  • Commentary (four slides).

Operating & Support Hazard Analysis: Transcript

Click here for the Transcript

Introduction

Hello everyone and welcome to the Safety Artisan; home of safety engineering training. I’m Simon and today we’re going to be carrying on with our series on Mil. Standard 882E system safety engineering.

Operating & Support Hazard Analysis

Today, we’re going to be moving on to the subject of operating and support hazard analysis. This is, as it says, task 206 under the standard. Operating and support hazard analysis, I’ll just call it O&S or OSHA (also O&SHA) for short. Unfortunately, that will confuse people if I call OSHA. Let’s call it O&S.

Topics for this Session

The purpose of O&S hazard analysis is to identify and assess hazards introduced by those activities and procedures and also to evaluate the adequacy of O&S procedures, processes, equipment, facilities, etc, to mitigate risks that have been already identified. A twofold task but a very big task. And as we’ll see, we’ve got lots of slides today on task description, and reporting, contracting, and commentary. As always, I present the full text as is of the task, which is copyright free, but I’m only going to talk about the things that are important. So, we’re not going to go through every little clause of the standard that would be pointless.

O&S Hazard Analysis (T206)

Let’s get started with the purpose. As we’ve already said, it’s to identify and assess those hazards which are introduced by operational and support activities and procedures and evaluate their adequacy. So, we’re looking at operating the system, whatever it may be- And of course, this is a military standard, so we assume a military system, but not all military systems are weapon systems by any means. Not all are physical systems. So, there may be inventory management systems, management information systems, all kinds of stuff. So, does operating those systems and just supporting them (maintaining them are resupplying them, disposing of them, etc.,) does that create any hazards or introduce any hazards? And how do we mitigate? That’s the purpose of the task.

Task Description (T206) #1

Let’s move on to the task description. Again, we’re assuming a contractor is performing the analysis, but that’s not necessarily the case. For this task, this actually says this typically begins during engineering and manufacturing development, or EMD.  So, we’re assuming an American style lifecycle for a big system and EMD comes after concept and requirements development. So, we are beginning to move into the very expensive stage of development for a system where we begin to commit serious money. It’s suggesting that O&SHA can wait until then which is fine in general unless you’ve identified any particularly novel hazards that will need to be dealt with earlier on. As it says, it should build on design hazard analyses, but we’ll also talk about the case later on when there is no design hazard analyses. And the O&SHA shall identify requirements or alternatives or eliminating hazards, mitigating risks, etc. This is one of those tasks where the human is very important – In fact, dominant to be honest. Both as a source of hazards and the potential victim of the associated risks. A lot of human-centric stuff going on here.

Task Description (T206) #2

As always, we’re going to think about the system configurations. We’re going to think about what we’re going to do with the system and the environment that we’re going to do it in. So, a familiar triad and I know I keep banging on about this, but this really is fundamental to bounding and therefore evaluating safety. We’ve got to know what the system is, what we’re doing with it, and the environment in which we’re doing it. Let’s move on.

Task Description (T206) #3

Again, Human Factors, regulatory requirements, and particularly specified personnel requirements need to be thought of. Particularly for operating and support, we need to take into account the staffing and personnel concept that we have. It’s frighteningly easy to produce a system that needs so much maintenance, for example, or support activity that it is unaffordable. And lots and lots of military systems and, it must be said, government and commercial systems in the past have come in that required enormous amounts of support, which soon proved to be unaffordable or no one would sign up to the commitment required. So, lots of projects have simply died because the system was going to be too expensive to sustain. That’s a key point of what we’re doing with O&S here. It’s not just about health and safety. It’s about health and safety, which is affordable.

We also need to look at unplanned events. So, not just designed in things, but things introduced- It says human errors. Again, I’m going to re-emphasize it’s erroneous human action because human error makes it sound like a human is at fault. Whereas very often it’s the design or the concept or the requirements that are at fault and place unacceptable burdens on the human being. Again, lots of messy systems seen in the past, which didn’t quite work and we just kind of expected the operator to cope. And most of the time they cope and then every so often they have a bad day at the office or a bunch of factors come together and lots of people die. And then we blame the human. Well, it’s not the human’s fault at all. We put them in that position. And as always, we need to look at past- Past evaluations of related legacy systems and support operations. If you have good data about legacy systems or about similar systems that your organization or another organization has operated, then that’s gold dust. So, do make an effort to get hold of that information if you can. Maybe a trade association or some wider pan organization body can help you there.

Task Description (T206) #4

At a minimum, we’ve got to identify activities involving known hazards. This assumes that we’ve done some hazard analysis in the past, which is very important. We always need to do that. I’ll come back to that commentary. Secondly, changes needed in requirements, be they functional requirements – what we want the system to do. Or design requirements, if we put constraints on how the system may do it for whatever it may be, hardware, software, support equipment, whatever to make those hazards and risks more manageable. Requirements for safety features – so requirements for engineered features and devices, equipment, because always, in almost any jurisdiction, we will have a hierarchy of control that recognizes that designed and engineered in safety features are more effective than just relying on people to get it right. And then we’ve also got to communicate to people the hazards associated with the system. Warnings, cautions, and whatever special emergency procedures might be required associated with the system. Again, that’s something that we see reinforced in law and regulations in many parts of the world. This is all good stuff. It’s accepted good practice all across the world.

Task Description (T206) #5

Moving on, we also need to think about how are we going to move the system around and the associated spares and supplies? How are we going to package them, handle them, stole them, transport them? Particularly if there are hazardous materials, etc, etc, involved. That’s the next part, G. Again, training requirements. We’re thinking about a human-centric approach. Whatever we expect people to do, they’ve got to be trained in how to do it. Point I, we’ve got to include everything, whether it’s developmental or non-developmental terms. We can’t just ignore stuff because it’s GFE or it’s off the shelf. It doesn’t mean it can never go wrong. Far from it. Particularly if we are putting stuff together that’s never been put together before in a novel combination or in a novel environment. Something that might be perfectly safe and stable in an air-conditioned office might start to do odd things in a much more corrosive and uncontrolled environment, let’s say.

We need to think about what modes might the system be potentially hazardous when under operative control. Particularly, we might think about degraded modes of operation. So, for whatever reason, a part of the system has gone wrong or the system has got into an operating environment within which it doesn’t operate as well as it could. It’s not in an optimal operating environment or state. The human being in control of it, we’re assuming, has still got to be able to operate the system, even if it’s only to shut it down or to get it back into a safer state or safer environment. We’ve got to think about all of those nuances.

Then because we’re talking about support as well, we need to think about a related legacy systems, facilities and processes which may provide background information. Also, of course, the system presumably will very often be operating alongside other systems or it will be supported by all systems maybe that exist or being procured separately. So, we’ve got to think about all those interactions as well and all those potential contributions. As you can see, this is quite a wide-ranging broadly scoped task.

Task Description (T206) #6

Finally, on this section, the customer/the end-user/or whoever may specify some specific analysis techniques. Very often they will not. So, whoever is doing the analysis, be they a contractor or third party outside agency, needs to make sure that whatever they propose to do is going to be acceptable to the program manager. In the sense that it is going to be compatible and relevant and useful. And then finally, the contractor has got to do some O&SHA at the appropriate time but maybe more detailed data will come along later. In which case that needs to be incorporated and also operational changes.

An absolute classic [situation] with military and non-military systems is; the system gets designed, it goes into test and evaluation and we discover that things- assumptions that were made during development- don’t actually hold up. The real world isn’t like that or whatever it might be and we find we’re making changes- making changes in assumptions. Those need to be factored in which, sadly, is often not done very well. So, that’s an important point to think about. What’s my change control mechanism and how will the people doing the and O&SHA find out about these changes? Because very often it’s easy to assume that everybody knows about this stuff but when you start making assumptions, the truth is that it very often goes adrift.

Reporting (T206) #1

Let’s talk about reporting- Just a couple of slides here. In the reporting, there’s some fairly standard stuff in here, the physical and functional characteristics of the system- that’s important. Again, we might assume that everybody knows what they are, but it’s important to put them in. It may be that the people doing the analysis were given a different system description to the people developing the system, to the people doing the personnel planning, etc. All the different things that have to be brought together, we need to make sure that they join up again. It’s too easy to get that wrong. Reinforcing the point I made on the previous slide, as more detailed descriptions and specifications come in that needs to be supplied when it becomes available and provided.

Hazard analysis methods and techniques. What techniques are we using? Give a description. If you’re doing it to a particular standard, so much the better. Great- that saves a lot of paper. What assumptions that we made? What data, both qualitative and quantitative have we used to support analysis? That all needs to be declared. By the way, one of the reasons is to be declared is that when things change- not if- that’s when these assumptions and the data and the techniques get exposed. So, if there are changes, if we don’t have this kind of information declared, we can’t assess the impact changes. And it gets even more difficult to keep up with what’s going on.

Reporting (T206) #2

And then hazard analysis results. Again, the leading particulars of the results should be recorded in the hazard tracking system, the HTS, or hazard log, or risk register- whatever you want to call it. But there will be more detailed information that we wouldn’t want to clutter up the risk register with and we also need to provide warnings, cautions, and procedures to be included in maintenance manuals, training courses, operator manuals, etc. So, we’re going to or we’re probably going to generate an awful lot of data out of this task and that needs to be provided in a suitable format. Again, whoever the program manager on the client-side, or is the end-user representation, needs to think about this stuff quite early on.

Contracting #1

That leads us neatly on to contracting. Now, this task, in theory, can be specified a little bit down the track, after the program started. In practice, what you find is program managers tried to specify everything up front in a single contract for various reasons.

There are good reasons for doing that sometimes. Also, there are bad reasons but I’m not going to talk about this session. We’ll have a talk about planning your system safety program in another session. There’s a lot of nuances in there to be considered.

Just sticking to this task, identification of functional disciplines – who do we need to get involved in order to do this work properly? It’s likely that the safety team if you have one, may not have relevant operating experience or relevant sustainment experience for this kind of system. If they do, that’s fantastic but that doesn’t negate the read the requirement to get the end-user represented and involved. In fact, that’s a near legal requirement in Australia, for example, and in some other jurisdictions. We need to get the end-users involved. We need the discipline specialist to get involved. Typically, your integrated logistic support team, your reliability people, your maintainability, and your testability people, if you have those disciplines. Or maybe you’re calling them something else, it doesn’t really matter.

We need to know what are the reporting requirements. What, if any, analysis methods and techniques do we desire to be used? Maybe the client or end-user has got to jump through some regulatory hoops and therefore they need specific analysis work and safety results to be done and produced. If that’s the case, then that needs to be specified in the contract. And what data is to be generated in what format? And how is it to be reported on when, etc? Considering the hazard tracking system, etc? And then the client may also select or specify known hazards, known hazardous areas, or other specific items to be examined or excluded because maybe it’s being covered elsewhere or we don’t expect the contractor to be able to do this stuff. Maybe we need to use a specialist organization. Again, maybe a regulator has directed us to do so. So, all of these things need to be thought about when we’re putting together the contract requirements for task 206.

Contracting #2

Again, I say this every time, we need to include all items within the scope of the system and the environment, not just developmental stuff. In fact, these days, maybe the majority of programs that I am seeing are mostly non-developmental. So, we’re taking lots of COTS stuff, GFE components, and putting it all together. That’s all going to be included, particularly integration.

We need to think about legacy and related processes and the hazard analysis associated with them if we can get them. They should be supplied to whoever is doing the work and an analyst should be directed to review them and include lessons learned.

Then, reinforcing the previous point that has a tracking system- How will information reported in this task be correlated with tasks and analyses that are being done maybe elsewhere or by different teams? And the example here is 207 health hazard analysis. I’ll talk a little bit about the linkages between the two later. But it’s quite likely in this sort of area there will be large groups of people thinking about operations and maintenance and support. Very often those groups are very different. Sometimes they don’t even talk to each other. That’s the culture in different organizations. You don’t see airline pilots hanging around with baggage handlers very much, do you, down the pub for whatever reason? Different set of people- they don’t always mix very much. And again, you may also have different specialist disciplines, especially the Human Factors people. Again, you’ve got to tie everything in there. So, there’s going to be lots of interfaces in this kind of task that they’ve got to be managed.

Point I – concept of operations. Yes, that’s in every task. You’ve got to understand what we intend to do with this system or what the end-user intends to do with the system in order to have some context for the analysis.

And then finally, what risk definitions and what risk matrix are we using? If we’re not using the standard 882 matrix, then what are we doing?

Commentary #1

I’ve got four slides of commentary now – a number of things to say about Task 206.

Now, I’ve picked an Australian example. So, Task 206 ties in very neatly with Australian WHS requirements. I suspect Australian WHS requirements have been strongly influenced by American OSHA and system safety practices. In Australia, we are heavily influenced by the US approach. This standard and legal requirements in Australia, and in many other states and territories let’s be honest, do tie in nicely with the standard. Although not always perfectly, you’ve got to remember that. So, we do need to focus on operations and support activities. That’s a big part of WHS, thinking about all relevant activities and cradle to grave – the whole life of the system. We need to think about the working environment, the workplace. We need to think about humans as an integral part of the system, be they operators or maintainers, suppliers, other kinds of sustainers. And we need to be providing relevant information on hazards, risks, warnings, trainings, and procedures, and requirements for PPE, and so on and so forth to workers.

So, task 206 is going to be absolutely vital to achieving WHS compliance in Australia and compliance with health and safety legislation and regulations in many parts of the world. In the US and UK and I would say in virtually all developed nations. So, this is a very important task for achieving compliance with the law and regulations. It needs to get the requisite amount of attention- It doesn’t always. People so often on a program during procurement and acquisition development, the technical system is the sexy thing. That’s the thing that gets all the attention, especially early on. The operating and particularly the support side tends to get neglected because it’s not so sexy. We don’t buy a system to support it after all do we? We buy a system to do a job. So, we get the operators in and we get their input on how to optimize the system to do the job most cost-effectively and with most mission effectiveness that we can get out of it. We don’t often think about support effectiveness. But to achieve WHS compliance or the equivalent this is a very important task so we will almost always need to do it.

Commentary #2

The second item to think about – what is going to be key for the maintenance support side is a technique called Job Safety Analysis or Job Hazard Analysis. I’ve highlighted a couple of sources of information there, particularly I would recommend going to the American www.OSHA.gov site and the guidance that they provide on how to do a job hazard analysis. So, use that or use something else if something different is specified in the jurisdiction you’re working it, then go ahead and use that. But if you don’t have any [guidance] on what to do, this will help you.

This is all about – I’ve got a task to do, whatever it might be doing, how do I do it? Let’s analyse this step-by-step, or at least in reasonable size chunks, thinking about how we do the tasks that need to be done. Now, there’s the operator side, and then, of course, we’re always dealing with human beings working on the system or working with the system. So, we’re going to be seeing potentially a lot of Human Factors type techniques being relevant. And there are lots of tasks that we can think about, Hierarchical Task Analysis and that kind of approach is going to fit in with the Job Hazard Analysis as well. Those are going to link together quite well. There will also be things like workload analysis. Particularly for the operators, if we’re asking the operator to do a lot and to maintain a particular level of concentration or respond rapidly, we need to think about workload and too much workload and too little workload can make things worse.

There are lots of techniques out there, I’m not going to talk about Human Factors here. I’m going to be putting on a series on Human Factors techniques in cooperation with a specialist in that area. So, I’m not going to say more here.

For certain kinds of operators, let’s say, pilots, people navigating a ship and so on, drivers, there will be well-established ways that those operators are trained the way they have to operate. There will often be a legal framework and a regulatory framework that says how they have to operate. And then that may direct a particular kind of analysis to be done or a particular approach to be taken for how operators do their jobs. But equally, there is a vast range of operator roles in industry, in chemical plants. Various specialist operating roles where there’s an industry-specific approach to doing things. Or indeed the general approach may be left up to whoever is developing the system. So, there’s a huge range of approaches here that are going to be largely dictated by the concept of operations and also an awareness of what is relevant law, regulation, and good practice in a particular industry, in a particular situation. That’s where doing your Task 203, your safety requirements analysis really kicks in. It’s a very broad subject we’re covering here. You’ve got to get the specialist in to do it well.

Contracting #3

Now, I mention that these days we’re seeing more and more legacy and COTS systems being used and repurposed. Partly to save time and money. We’re not developing mega systems as often as we used to, particularly in defence, but also in many other walks of life as well. So, we may find ourselves evaluating a system where very little technical hazard analysis has been done because there are no developmental items and it’s even difficult to do analysis on legacy or a COTS system because we cannot get the data to do so. Perhaps we can’t get the data for commercial reasons, contractual reasons.

Or maybe we’ve got a legacy system that was developed in a different jurisdiction and whatever information is available with it just doesn’t fit the jurisdictional regulatory system that we’ve got to work in where we want to operate the system. This is very common. Australia, for example, [acquires] a lot of systems from abroad, which have not been developed in line with how we normally do things.

We could in theory just do Task 206 if there was no developmental hazard analysis to do but that’s not quite true. At a minimum, we will always need to do some Preliminary Hazard Listing and hazard analysis – that’s Tasks 201 and 202 respectively. And we will very definitely need to do some System Requirements Hazard Analysis, Task 203, to understand what we need to do for a particular system in a particular application, operating environment, and regulatory jurisdiction. So, we’re always going to have to do those and we may well have to look at the integration of COTS things and do some system-level analysis. That’s 204. We’re definitely going to need to do the early analyses. In fact, the client and the end-user representatives should be doing 201, 202 and 203 and then we may be in a position to finish things off with 206 for certain systems.

Contracting #4

Now, having said that, I’ve mentioned already that Task 206 can be very broad in scope and very wide-ranging. There’s a danger that we will turn Task 206 into a bottomless pit into which we pour money and effort and time without end. So, for most systems, we cannot afford to just do O&SHA across the board without any discernment or any prioritization.

So, we need to look at those other hazard analyses and prioritize those areas where people could get hurt. Particularly we should be using legacy and historical data here to say “What does – in reality, what does hurt people when looking after these systems or operating systems?” Again, as I’ve said before, in many industries there is a standard industry approach or good practice to how certain systems are operated, and maintained, and supported. So, if there is a standard industry approach available – particularly if we can justify that by available historical data – if that [is as good] as doing analysis, then why not just use the standard approach? It’s going to be easier to make a SFARP or a ALARP argument that way anyway. And why spend the money on analysis when we don’t have to? We could just spend the money on actually making the system safer. So, let’s not do analysis for the sake of doing analysis.

Also, there’s a strong synergy between the later tasks in the 200 series. There’s a strong linkage between this Task 206 and 207, which is Health Hazard Analysis. Also, there can be a strong linkage between Task 210, which is the Environmental Hazard Analysis. So, this trio of tasks focuses on the impact on living things, whether they be human beings or animals and plants and ecosystems and very often there’s a lot of overlap between them. For example, hazardous chemicals that are dangerous for humans are often dangerous for animals and plants and watercourses and so on and so forth. I’ll be talking about that more in the next session on Task 207.

One word of warning, however. Certainly, in Australia, we have got fixated on hazardous chemicals because we’ve had some very high-profile scandals involving HAZCHEM in the past. Now, there’s nothing wrong, of course, with learning from experience and applying rigorous standards when we know things have gone wrong in the past. But sometimes we go into a mindset of analysis for analysis sake. Dare I say, to cover people’s backsides rather than to do something useful. So, we need to focus on whether the presence of a HAZCHEM could be a problem. Whether people get exposed to it, not just that it’s there.

Certain chemicals may be quite benign in certain circumstances, and they only become dangerous after an emergency, for example. There are lots of things in the system that are perfectly safe until the system catches fire. Then when you’re trying to dispose or repair a fire damage system that can be very dangerous, for example. So, we need to be sensible about how we go about these things. Anyway, more on that in the next session.

Copyright Statement

That’s the commentary that I have on Task 206. As we said, it links very tightly with other things and we will talk about those in later sessions. I just like to point out that the “italic text in quotations” is from the Mil. standard. That is copyright free as most American government standards are. However, this presentation and my commentary, etc. are copyright of the Safety Artisan 2020.

For More …

Now, for all lessons and resources, please do visit the www.safetyartisan.com. Now, as you’ll notice, it’s an https – it’s a secure website.

End: Operating & Support Hazard Analysis

So, that is the end of the lesson and it just remains for me to say thank you very much for your time and for listening. And I look forward to seeing you again soon. Cheers.

Categories
Mil-Std-882E Safety Analysis

Functional Hazard Analysis

In this full-length (40-minute) session, The Safety Artisan looks at Functional Hazard Analysis, or FHA, which is Task 208 in Mil-Std-882E. FHA analyses software, complex electronic hardware, and human interactions. We explore the aim, description, and contracting requirements of this Task, and provide extensive commentary on it. (We refer to other lessons for special techniques for software safety and Human Factors.)

This is the seven-minute demo; the full version is 40 minutes long.

Topics: Functional Hazard Analysis

  • Task 208 Purpose;
  • Task Description;
  • Update & Reporting
  • Contracting; and
  • Commentary.

Transcript: Functional Hazard Analysis

Click here for the Transcript

Introduction

Hello, everyone, and welcome to the Safety Artisan; Home of Safety Engineering Training. I’m Simon and today we’re going to be looking at how you analyse the safety of functions of complex hardware and software. We’ll see what that’s all about in just a second.

Functional Hazard Analysis

I’m just going to get to the right page. This, as you can see, functional hazard analysis is Task 208 in Mil. Standard 882E.

Topics for this Session

What we’ve got for today: we have three slides on the purpose of functional hazard analysis, and these are all taken from the standard. We’ve got six slides of task description. That’s the text from the standard plus we’ve got two tables that show you how it’s done from another part of the standard, not from Task 208. Then we’ve got update and recording, another two slides. Contracting, two slides. And five slides of commentary, which again include a couple of tables to illustrate what we’re talking about.

Functional Purpose HA #1

What we’re going to talk about is, as I say, functional hazard analysis. So, first of all, what’s the purpose of it? And in classic 882 style, Task 208 is to perform this functional hazard analysis on a system or subsystem or more than one. Again, as with all the other tasks, it’s used to identify and classify system functions and the safety consequences of functional failure or malfunction. In other words, hazards.

Now, I should point out at this stage that the standard is focused on malfunctions of the system. The truth is in the real world, that lots of software-intensive systems have been involved in accidents that have killed lots of people, even when they’re functioning as intended. That’s one of the short-sightedness of this Mil. Standard is that it focuses on failure. The idea that if something is performing as specified, that either the specification might be wrong or there might be some disconnect between what the system is doing and what the human expects – The way the standard is written just doesn’t recognize that. So, it’s not very good in that respect. However, bearing that in mind, let’s carry on with looking at the task.

Functional HA Purpose #2

We’re going to look at these consequences in terms of severity – severity only, we’ll come back to that – for the purpose of identifying what they call safety-critical functions, safety-critical items, safety-related functions, and safety-related items. And a quick word on that, I hate the term ‘safety-critical’ because it suggests a sort of binary “Either it’s safety-critical. Yes. Or it’s not safety-critical. No.” And lots of people take that to mean if it’s “safety-critical, no,” then it’s got nothing to do with safety. They don’t recognize that there’s a sort of a sliding scale between maximum safety criticality and none whatsoever. And that’s led to a lot of bad thinking and bad behaviour over the years where people do everything they can to pretend that something isn’t safety-related by saying, “Oh, it’s not safety-critical, therefore we don’t have to do anything.” And that kind of laziness kills people is the short answer.

Anyway, moving on. So, we’ve got these SCFs, SCIs, SRFs, SRIs and they’re supposed to be allocated or mapped to a system design architecture. The presumption in this – the assumption in this task is that we’re doing early – We’ll see that later – and that system design, system architecture, is still up for grabs. We can still influence it. Often that is not the case these days. This standard was written many years ago when the military used to buy loads of bespoke equipment and have it all developed from new. That doesn’t happen anymore so much in the military and it certainly doesn’t happen in many other walks of life – But we’ll talk about how you deal with the realities later. And they’re allocating these functions and these items of interest to hardware, software and human interfaces. And I should point out, when we’re talking about all that, all these things are complex. Software is complex, human is complex, and we’re talking about complex hardware. So, we’re talking about components where you can’t just say, “Oh, it’s got a reliability of X, and that’s how often it goes wrong” because those type of simple components that are only really subject to random failure, that’s not what we’re talking about here. We’re talking about complex stuff where we’re talking about systematic failure dominating over random, simple hardware failure. So, that’s the focus of this task and what we’re talking about. That’s not explained in the standard, but that’s what’s going on.

Functional HA Purpose #3

Now, our third slide on purpose; so we use the FHA to identify consequences of malfunction or functional failure, lack of function. As I said just now, we need to do this as early as possible in the systems engineering process to enable us to influence the design. Of course, this is assuming that there is a systems engineering process – that’s not always the case. We’ll talk about that at the end as well. And we’re going to identify and document these functions and items and allocate and it says partition them in the software design architecture. When we say partition, that’s jargon for separate them into independent functions. We’ll see the value of that later on. Then we’re going to identify requirements and constraints to put on the design team to say, “To achieve this allocation in this partitioning, this is what you must do and this is what you must not do”. So again, the assumption is we’re doing this early. There’s a significant amount of bespoke design yet to be done.

Task Description (T208) #1

Moving on to task description. It says the contractor, but whoever’s doing the analysis has to perform and document the FHA, to analyse those functions, as it says, with the proposed design. I talked about that already so we’ll move on.

It’s got to be based on the best available data, including mishap data. So, accident/incident data, if you can get it from similar systems and lessons learned. As I always say in these sessions, this is hard to do, but it’s really, really valuable so do put some effort into trying to get hold of some data or look at previous systems or similar systems. We’re looking at inputs, outputs, interfaces and the consequences of failure. So, if you can get historical data or you can analyse a previous system or a similar system, then do so. It will ultimately save you an awful lot of money and heartache if you can do that early on. It really is worth the effort.

Task Description (T208) #2

At a minimum, we’ve got to identify and evaluate functions and to do that, we need to decompose the system. So, imagine we’ve got this great big system. We’ve got to break it down into subsystems of major components. We’ve got to describe what each subsystem and major component does, its function or its intended function. Then we need a functional description of interfaces and thinking about what connects to what and the functional ins and outs. I guess pretty obvious stuff  – needs to be done.

Task Description (T208) #3

And then we also need to think about hazards associated with, first of all, loss of function. So, no function when we need it. Now, we have degraded functional malfunction and sort of functioning out of time or out of sequence. So, we’ve got different kinds of malfunctions. What we don’t have here is function when not required. So, the system goes active for some reason and does something when it’s not meant to. Now, if we add that third base and we’ve got a functional failure analysis.

Essentially here, we’re talking about a functional failure analysis, maybe something a bit more sophisticated, like a HAZOP. And the HAZOP is more sophisticated because instead of just those three things that can go wrong, we think about we’ve got lots of guide words to help us think about ‘out of time, out of sequence’. So, too early, too late, before intended, after intended, whatever it might be. And there are there variations on HAZOP called computer HAZOP, or CHAZOP, where people have come up with different keywords, different prompt words, to help you think about software in data-intensive systems. So, that’s a possible technique to use here.

And then when we’re thinking about these hazards that might be generated by malfunction, or functional failure in its various forms, we need to think about, “What’s the next step in the mishap sequence? In the accident sequence? And what’s the final outcome of the accident sequence?” And that’s very important for software because software is intangible. It has no physical form. On its own, in isolation, software cannot possibly hurt anyone. So, you’ve got to look at how the software failure propagates through the system into the real world and how it could harm people. So, that’s a very important prompt that that last sentence in yellow there.

Task Description (T208) #4

And we carry on. We need to assess the risk with failure of a function subsystem or component. We’re going to do so using the standard 882 tables, tables one and two, and risk assessment codes in table three, unless we come up with our own tailored versions of those tables and that matrix and that’s all approved. In reality, most people don’t tailor this stuff. They should make it appropriate for the system, but they rarely do.

Table I and II

So just to remind us what we’re talking about, here’s table one and two. Table one is severity categories ranging from catastrophic, which could kill somebody – a catastrophic outcome – down to negligible, where we’re talking cuts and bruises – very, very, very minor injuries.

And then table two, probability levels. We’ve got everything from frequent down to eliminated – There’s no hazard at all because we’ve eliminated. It will never happen in the lifetime of the universe. So, it really is a zero probability. We’ve got frequent down to improbable and then in the standard, we’ve got a definition for these things in words, for a single item and also for a fleet or inventory of those items, assuming that there’s a large number of them. And that’s very useful. That helps us to think about how often something might go wrong per item and per fleet.

Table III

So, that’s tables one and two, we put them together, the severity and the probability to give us table three. As you can see, we’ve got probability down the left-hand side and at the bottom, if we’ve eliminated the hazard, then there is no severity. The hazard is completely eliminated. So, forget about that row. Then everything else we’ve got frequent down to improbable, probability. And we’ve got catastrophic down to negligible. Together those generate the risk assessment code, which is either high, serious, medium or low. That’s the way this standard defines things. Nothing is off-limits. Nothing is perfect except for elimination. We’ve just defined a level of risk and then you have to make up rules about how you will treat these levels of risk. The standard does some of that for you, but usually, you’ve got to work out depending on which jurisdiction you’re in legally, what you’re required to do about different levels of risk.

Now this table on its own, I’ll just mention, is not helpful in a British or Australian jurisdiction where we have to reduce or eliminate risks SOFARP. The table on its own won’t help you do that, because this is just an absolute level of risk. It’s not considering what you could have done to make it better. It’s just saying where we are. It’s a status report.

So, those are your tables one, two and three, as the standard describes them. That’s the overall method and we’re going to do what it says in Section four of the standard. In the main body of the standard, Section four talks about software and complex hardware and how we allocate these things.

Task Description (T208) #5

And then finally, I think on task description, an assessment of whether the functions identified are to be implemented in the design – sorry, of whether the functions are to be implemented in the design and map those functions into the components. And then it says functions allocated to software should be matched to the lowest level of technical design or configuration item. So, if you’ve got a software or hardware configuration item that is further subdivided into sub-items, then you need to go all the way down and see which items can contribute to that function and which can’t.

That’s an important labour-saving device, because if you’ve got  – you could have quite a large configuration item, but actually, only a tiny bit contributes to the hazard. So, that’s the only thing you need to worry about in theory. In reality, partitioning software is not as easy as the standard might suggest. However, if we can do a meaningful partition, then we could and should aim to have as little software safety-related as we possibly can. If nothing else, for cost in order to get the project in on time. So, the less criticality we have in our system, the better.

Task Description (T208) #6

So, we need to assess the software control category for each configuration item that’s been allocated a safety-significant software function (SSSF). Having assigned the SCC, we then have to work at the software criticality index for each of those functions and we’ll talk about how to do that at the end. Then from all of this work, we need to generate a list of requirements and constraints to include in the spec which, if they work, will eliminate the hazard or reduce the risk.

And the standard talks about that these could be in the form of fault tolerance, fault detection, fault isolation, fault annunciation or warning, or fault recovery. Now, this breakdown reveals – basically this is a reliability breakdown. So, in the world of reliability, we talk typically about fault tolerance, fault detection, warning, and recovery. Four things – I mean they split them down to five here. Now, software reliability is highly controversial. So really, this is a bit of a mismatch here. These reliability-based suggestions are not necessarily much use for software, or indeed for people sometimes. You may have to use other more typical software techniques to do this and in fact, the standard does point you to do that. But that’s for another session.

FHA Update & Records #1

So, we’ve done the FHA, or we’re doing the FHA. We’ve got to record it and we’ve got to update it when new information comes through. So, we’ve got to update the FHA as the design progresses or operational changes come in. We’ve got to have a system description of the physical and functional characteristics of the system and subsystems. And of course, for design complex items like software, context is everything. So, this is very important. Again, software in isolation cannot hurt anyone. You’ve got to have the context to understand what the implications might be. If we don’t have that, we’re stuffed pretty much. Then it goes on to say that when further documentation becomes available, more detail that needs to be supplied. So, don’t forget to ask for that in your contract and expect it as well and be ready to deal with it.

FHA Update & Records #2

 Moving on. When it comes to hazard analysis, method and techniques, we need to describe the method and the technique used for the analysis, what assumptions and what data was used in support of the analysis and this statement is pretty much in every single task so I’ll say no more. You’ve heard this before. Then again, analysis results need to be captured in the hazard tracking system and, as I’ve always said, usually the leading details, the top-level details, go in there has a tracking system. The rest of it goes into the hazard analysis report otherwise, you end up with a vast amount of data in your HTS and it becomes unwieldy and potentially useless.

Contracting #1

Contracting – Again, this is a pretty standard clause, or set of clauses, in a Mil. Standard 882 task. So, in our request for proposal and statement of work, we’ve got to ask for Task 208. We’ve got to point the analyst, the contractor, at what we want them to analyse particularly or maybe as a minimum. And what we don’t want to analyse, maybe because it’s been done elsewhere or it’s out of scope for this system.

We need to say what are data reporting requirements are considering Task 106, which is all about hazard tracking system or the hazard log or the risk register, whatever you want to call it. So, what data do we want? What format? What are the definitions, etc.? Because if you’re dealing with multiple contractors or you want data that is compatible with the rest of your inventory, then you’ve got to specify what you want. Otherwise, you’re going to get variability in your data and that’s going to make your life a whole lot harder downstream – Again, this is standard stuff.

And what are the applicable requirements, specifications and standards? Of course, this is an American standard so compliance with specifications, requirements and standards is all because that’s the American system.

Contracting #2

We need to supply the concept of operations, as I’ve said before, with a complex design. Especially software, context is everything. So, we need to know what we’re going to do with the system that the software is sat within. So, this system has got some functions, this is what we’re looking at in Task 208: What are those functions for? How do they to relate with the real world? How could we hurt people? And then if we got any other specific hazard management requirements. Maybe we’re using a special matrix because we’ve decided the standard matrix isn’t quite right for our system. Whatever we’re doing, if we’ve got special requirements that are not the norm for the vanilla standard, that we need to say what they are. Pretty straightforward stuff.

Commentary #1

We’re onto commentary, and I think we’ve got five slides of commentary today.

As it says, functional hazard analysis depends on systems engineering. So, if we don’t have good systems engineering, we’re unlikely to have good functional analysis. So, what do I mean by good systems engineering? I mean, that for the complete system – apart from things that we deliberately excluded for a good reason – but for the complete system we need or functions to be identified, we need those functions to be analysed and allocated correctly in accordance and rigorously and consistently. We need interface analysis, control, and we need the architecture of the design to be determined based on the higher-level requirements, all that work that we’ve done.

Now, if those things are not done or they’re incomplete, or they were done too late to influence the design architecture, then you’re going to have some compromised systems engineering. And these days, because we’re using lots of commercial off the shelf stuff, what you find is that your top-level design architecture is very often determined before you even start because you’ve decided you’re going to have an off the shelf this and you’re going to have a modified off the shelf that and you’re going to put them together in a particular way with a set of business rules, a concept of operations, that says this is how we’re going to use this stuff. And our new system interfaces with some existing stuff and we can’t modify the existing stuff.

So, that really limits what we can do with the design architecture. A lot of the big design decisions have already been taken before we even got started. Now, if that’s the case, then that needs to be recognized and dealt with. I’ve seen those things dealt with well. In other words, the systems engineering has been done recognizing those constraints, those things that that can’t be done. And I’ve seen it done badly in that figuratively speaking, the systems engineering team or the program manager, whoever has just given us a Gallic shrug and gone “Yeah, what the heck, who cares?” So, there’s this the two extremes that you can see.

Now, if the systems engineering is weak or incomplete, then you’re going to get a limited return on doing Task 208. Maybe there are some areas where you can do it on new areas, or maybe you’ve got a new interface that’s got to be worked up and created in order to get these things to talk to each other. Clearly, there is some mileage in doing that. You’re going to get some benefits from doing that in that area. But for the stuff that’s already been done, probably – Well, what what’s the point of doing systems engineering here? What does it achieve? So, maybe in those circumstances, it’s better – Well, in fact, I would say it’s essential to understand where systems engineering is still valid, where you are still going to get some results and where it isn’t. And maybe you just declare that scope; What’s in and out.

Or maybe you take a different approach. Maybe you go “OK, we’re dealing with a predominantly COTS system. We need a different way of dealing with this than the way the Mil. standard 882 assumes.” So, you’re going to have to do some heavy tailoring of the standard because 882 assumes that you’re determining all these requirements predesigned. If that’s not the case, then maybe 882 isn’t for you. Or maybe you just need to recognize you’re going to have to hack it about severely. Which in turn means you’ve got to know what you’re doing fundamentally. In which case the standard really is no longer fulfilling its role of guiding people.

Commentary #2

Moving on. Let’s assume that we are still going to do some Task 208. We’re going to determine some software criticality. We’re also going to determine some criticality for complex hardware. So, things whether it be software in complex electronics, so pre-programmed electronics, whatever that might be. First of all, as we said before, we’re going to determine the software control category and what that’s really saying is how much authority does the software have? And then secondly, we’re going to be looking at severity, which was table one. How severe is the worst hazard or risk that the software could contribute to? And these are illustrated in the next two slides. And we do a session or several sessions on software safety is coming soon. That will be elsewhere. I’m not going to go into massive detail here. I’m just giving you an overview of what the task requires.

Commentary #3: Software Control Categories 1-5

First of all, how do we determine software control category? So, there’s the table from the standard. We’ve got five levels of SCC.

At the top, we’ve got autonomous. Basically, the software does whatever it wants to and there’s no checks and balances.

Secondly, they’re semi-autonomous. The software is there’s one software system performing a function, but there are hardware interlocks and checks. And those hardware interlocks and checks, and whatever else that are not software, can work fast enough to prevent the accident happening. So, they can prevent harm. So, that’s semi-autonomous.

Then we’ve got redundant fault-tolerant where you’ve got an architecture typically with more than one channel, and maybe all channels are software controlled. Maybe there’s diversity in the software and there is some fault-tolerant architecture. Maybe a voting system or some monitoring system saying, “Well, Channel Three’s output is looking a bit dodgy” or “Something gone wrong with Channel two”. I’ll ignore the channel at fault, and I’ll take the good output from the channels that are still working and I’ll use that. So that’s that option. Very common.

Then we’ve got number four, which is influential. So, the software is displaying some information for a human to interpret and to accept or reject.

And then we’ve got five, which is no safety impact at all. Now, the problem is this: because it’s very easy to say, “The software just displays some information, it doesn’t do anything”. So, unless a human does something – so we don’t have to worry about the safety implications of that at all. Wrong! Because the human operator may be forced to rely on the software output by circumstances, there may not be time to do anything else. Or the human may not be able to work out what’s going on without using the software output. Or more typically, the humans have just got used to the software generating the correct information or even they interpret it incorrectly.

And a classic example of that was when the American warship, the USS Vincennes, shot down an airliner and killed three hundred people because the way the system was set up, the supposedly not safety-related radar system was displaying information not associated with the airliner, but associated with the with a military Iranian aircraft. And the crew got mixed up and shot down the airliner. So, that’s a risky one. Even though it’s down at number four, that doesn’t mean it’s without risk or without criticality.

Commentary #4

So, if we have the software control category, and that’s down the right-hand side – sorry down the left-hand side, one to five. And along the top, we have the severity category from catastrophic down to negligible. We can use that to determine the software criticality index, which varies from one most critical down to five least critical. It’s similar to the risk assessment code in the table three coloured matrix that I showed you earlier. So, we’ve made – the writers of the standard have made a determination for us based on some assessment that they’ve done saying, “Well, this is this is how we assess these different criticality levels”. Whether there is actually any real-world evidence supporting this assessment, I don’t know and I’m not sure anybody else does either. However, that’s the standard and that’s where we are.

Commentary #5

And so just to finish up on the commentary. Task 208 is focused on software engineering, also programmable electronics, complex hardware, but typically electronics with software functionality or logic functionality embedded within it. Now if all of that software, all that programmable electronic systems, if they’re all developed already, is there any point in doing Task 208? That’s the first step – it’s got to pass the “So what?” test.

Is it feasible to do 208 and expect to get benefits? If not, maybe you just do system and subsystem hazard analysis. That’s tasks 205 and 204, respectively. And we just look at the complex components and subsystems as a black box and say, “OK, what’s it meant to do? What are the interfaces?” Maybe that would be a better thing to do. Particularly bearing in mind that the software or the complex electronic system could be working perfectly well and we still get an accident because there’s been a misunderstanding of the output. Maybe it’s more beneficial to look at those interfaces and think about, “Well, in what scenarios could the human misunderstand? How do we how do we guard against that?”

It’s also worth saying that some particularly American software development standards, can work well with Mil. Standard 882 because they share a similar conceptual basis. For example, I’ve seen many, many times in the air world, the systems software system safety standard is 882 and the systems software standard is DO-178 (AKA ED12, it’s the same standard, just different labels). Now they work relatively well together because the concept underpinning 178 is very similar to 882. It’s American centric.

It’s all about, you put requirements on the software development and – this is sort of a cookbook approach – the standard assumes that if you use the right ingredients and you mix them up in the right way, then you’re going to get a good result. And that’s a similar sort of concept for 882 and the two work relatively well together, fairly consistently. Also because they’re both American, there’s a great focus on software testing. Certainly, in the earlier versions of DO-178, it’s exclusively focused on software testing. Things like source code analysis and other things – more modern techniques that have come in – they’re not recognized at all in earlier versions of 178 because they just weren’t around.

That focus on testing suits 882, because 882, generates lots of requirements and constraints which you need to test. What it’s not so good at is generating cases where you say, “Well if this goes wrong” or “If we’re at the edge of the envelope where we should be, let’s test for those edge of the envelope cases, let’s test that the software is working correctly when it’s outside of the operating envelope that it should be”. Now, that kind of thinking isn’t so strong in 882, nor in 178. So, there are some limitations there. Good practice, experienced practitioners will overcome those by adding in the smarts that the standards lack. But just to be aware, a standard is not smart. You’ve still got to know what you’re doing in order to get the most out of it.

So, maybe you’re buying software that’s predevelopment or that you’re using – you’re not in the States. You’ve got a European or an Asian Indian supplier or Japanese supplier or whatever. Maybe they’re not using American style techniques and standards. Is that – how well is that going to work with 882? Are they compatible? They might be, but maybe they’re not. So, that requires some thought. If they’re not obviously compatible, then what do you need to do to make that translation and make it work. Or at least understand where the gaps are and what you might do about it to compensate?

And I’ve not talked about data, but it is worth mentioning that with data-rich systems these days – and I heard just the other day, is it two quintillion bytes of data being generated every two days or something ridiculous? That was back in 2017. So, gigantic amounts of data being generated these days and used by computing systems, particularly artificial intelligence systems. So, the rigour associated with that data  – the things that we need to think about on data are potentially just as important as the software. Because if the software is processing rubbish data, you’re probably going to get rubbish results. Or at the very least unreliable results that you can’t trust. So, you need to be thinking about all of those attributes of your data; correct, complete, consistent, etc, etc. I mean, I probably need to do a session on that and maybe I will.

Copyright Statement

That’s the presentation. As you can see, everything in italics and quotes is out of the standard, which is copyright free. But this presentation is copyright of the Safety Artisan.

For More…

And you will find many more presentations and a lot more resources at the website www.safetyartisan.com. Also, you’ll find the paid videos on our Patreon page, which is www.patreon.com/SafetyArtisan or go to Patreon and search for the Safety Artisan.

End

Well, that’s the end of our presentation, and it just remains for me to say thanks very much for listening. Thanks for your time and I look forward to seeing you in the next session, Task 209. Looking forward to it. Goodbye.

End

Categories
Mil-Std-882E Safety Analysis

Sub-System Hazard Analysis

In this video lesson, The Safety Artisan looks at Sub-System Hazard Analysis, or SSHA, which is Task 204 in Mil-Std-882E. We explore Task 204’s aim, description, scope, and contracting requirements. We also provide value-adding commentary and explain the issues with SSHA – how to do it well and avoid the pitfalls.

This is the seven-minute demo, the full video is 40-minutes’ long.

Topics: Sub-System Hazard Analysis

  • Preamble: Sub-system & System HA.
  • Task 204 Purpose:
    • Verify subsystem compliance;
    • Identify (new) hazards; and
    • Recommend necessary actions.
  • Task Description (six slides);
  • Reporting;
  • Contracting; and
  • Commentary.
Transcript: Sub-System Hazard Analysis

Introduction

Hello, everyone, and welcome to the Safety Artisan, where you will find professional, pragmatic, and impartial instruction on all things system safety. I’m Simon – I’m your host for today, as always and it’s the fourth of April 22. With everything that’s going on in the world, I hope that this video finds you safe and well.

Sub-System Hazard Analysis

Let’s move straight on to what we’re going to be doing. We’re going to be talking today about subsystem hazard analysis and this is task 204 under the military standard 882E. Previously we’ve done 201, which was preliminary hazard identification, 202, which is preliminary hazard analysis, and 203, which is safety requirements hazard analysis. And with task 204 and task 205, which is system has analysis, we’re now moving into getting stuck into particular systems that we’re thinking about, whether they be physical systems or intangible. We’re thinking about the system under consideration and I’m really getting into that analysis.

Topics for this Session

So, the topics that we’re going to cover today, I’ve got a little preamble to set things in perspective. We then get into the three purposes of task 204. First, to verify compliance. Secondly, to identify new hazards. And thirdly, to recommend necessary actions. Or in fact, that would be recommend control measures for hazards and risks. We’ve got six slides of task description, a couple of slides on reporting, one on contracting, and then a few slides on some commentary where I put in my tuppence worth and I’ll hopefully add some value to the basic bones of the standard. It’s worth saying that you’ll notice that subsystem is highlighted in yellow and the reason for that is that the subsystem and system hazard analysis tasks are very, very similar. They’re identical except for certain passages and I’ve highlighted those in yellow. Normally I use a yellow highlighter to emphasize something I want to talk about. This time around, I’m using underlining for that and the yellow is showing you what these different for subsystem analysis as opposed to system. And when you’ve watched both sessions on 204 and 205, I think you’ll see the significance of why I’ve done.

Preamble – Sub-system & System HA

Before we get started, we need to explain the system model that the 882 is assuming. If we look on the left-hand side of the hexagons, we’ve got our system in the centre, which we’re considering. Maybe that interfaces with other systems. They work within operating environment; hence we have the icon of the world, and the system and maybe other systems are there for a purpose. They’re performing some task; they’re doing some function and that’s indicated by the tools. We’re using the system to do something, whatever it might be.

Then as we move to the right-hand side, the system is itself broken down into subsystems. We’ve got a couple here. We’ve got sub-system A and B and then A further broken down into A1 and A2, for example. There’s some sort of hierarchy of subsystems that are coming together and being integrated to form the overall system. That is the overall picture that I’d like to bear in mind while we’re talking about this. The assumption in the 882, is we’re going to be looking at this subsystem hierarchy bottom upwards, largely. We’ll come on to that.

System Requirements Hazard Analysis (T204)

Purpose of the task, as I’ve said before, it’s threefold. We must verify subsystem compliance with requirements. Requirements to deal with risk and hazards. We must identify previously unidentified hazards which may emerge as we’re working at a lower level now. And we must recommend actions necessary. That’s further requirements to eliminate all hazards or mitigate associated risks. We’ll keep those three things in mind and that will keep coming up.

Task Description (T204) #1

The first of six slides on the task description. Basically, we are being told to perform and document the SSHA, sub-system hazard analysis. And it’s got to include everything, whether it be new developments, COTS, GOTS, GFE, NDI, software and humans, as we’ll see later. Everything must be included. And we’re being guided to consider the performance of the subsystem: ‘What it is doing when it is doing it properly’. We’ve got to consider performance degradation, functional failures, timing errors, design errors or defects, and inadvertent functioning – we’ll come back to that later. And while we’re doing analysis, we must consider the human as a component within the subsystem dealing with inputs and making outputs. If, of course, there is an associated human. We’ve got to include everything, and we’ve got to think about what could go wrong with the system.

Task Description (T204) #2

The minimum that the analysis has got to cover is as follows. We’ve got to verify subsystem compliance with requirements and that is to say, requirements to eliminate hazards or reduce risks. The first thing to note about that is you can’t verify compliance with requirements if there are no requirements. if you haven’t set any requirements on the subsystem provider or whoever is doing the analysis, then there’s nothing to comply with and you’ve got no leverage if the subsystem turns out to be dangerous. I often see it as it gets missed. People don’t do their top-down systems engineering properly; They don’t think through the requirements that they need; and, especially, they don’t do the preliminary hazard identification and analysis that they need to do. They don’t do Task 203, the SRHA, to think about what requirements they need to place further down the food chain, down the supply chain. And if you haven’t done that work, then you can’t be surprised if you get something back that’s not very good, or you can’t verify that it’s safe. Unfortunately, I see that happen often, even on exceptionally large projects. If you don’t ask, you don’t get, basically.

We’ve got two sub-paragraphs here that are unique to this task. First, we’ve got to validate flow down of design requirements. “Are these design requirements valid?”, “Are they the right requirements?” From the top-level spec down to more detailed design specifications for the subsystem. Again, if you haven’t specified anything, then you’ve got no leverage. Which is not to say that you have to dive into massive detail and tell the designer how to do their job, but you’ve got to set out what you want from them in terms of the product and what kind of process evidence you want associated with that product.

And then the second sub-paragraph, you’ve got to ensure design criteria in the subsystem specs have been satisfied. We need to verify that they’re satisfied, and that V and V of subsystem mitigation measures or risk controls have been included in test plans and procedures. As always, the Mil. standard 882 is the American standard, and they tend to go big on testing. Where it says test plans and procedures that might be anything – you might have been doing V and V by analysis, by demonstration, by testing, by other means. It’s not necessarily just testing, but that’s often the assumption.

Task Description (T204) #3

We must also identify previously unidentified hazards because we are now down at a low level of detail in a subsystem and stuff probably will emerge at that level that wasn’t available before. First, number one, we’ve got to ensure the implementation of subsystem design requirements and controls. And ensure that those requirements and controls have not introduced any new hazards, because very often accidents occur. Not because the system has gone wrong – the system is working as advertised – but the hazards with normal operation maybe just weren’t appreciated and guarded against or we just didn’t warn the operators that something might happen that they needed to look out for. A common shortfall, I’m afraid.

And number two, we’ve got to determine modes of failure down to component failure and human errors, single points of failure, common-mode failures, effects when failures occur in components, and from functional relationships. “What happens if something goes wrong over on this side of the system or subsystem and something else is happening over here?” What are those combinations? What could result? And again, we’ve got to consider hardware and software, including all non-developmental type stuff, and faults, and occurrences. Again, I see very often, buyers/purchases don’t think about the off the shelf stuff in advance or don’t include it. And then sometimes also you see contractors going “This is off the shelf, so we’re not analysing it.” Well, the standard requires that they do analyse it to the extent practicable. And they’ve got to look at what might go wrong with all of this non-development to stuff and integrate the possible effects and consider. That’s another common gotcha, I’m afraid. we do need to think about everything, whether it’s developmental or not.

Task Description (T204) #4

And then part C, recommending actions necessary to eliminate hazards if we can. Very often we can’t, of course, and we have to mitigate. We must reduce or minimize the associated risk of those hazards. In terms of the harm that might come to people. We’ve got to ensure that system-level hazards, it says attributed. Maybe we believe when we did the earlier analysis that the subsystem could contribute to a higher-level hazard, or maybe we’ve allocated some failure budget to this particular subsystem, which it has got to keep to if we’re going to meet the higher-level targets. You can imagine lots of these subsystems all feeding up a certain failure rate and different failure modes. And overall, when you pull it all together, we may have to meet some target or reduce the number of failures in their propagation upwards in order to manage hazards and risks. We’ve got to make sure that we’ve got adequate mitigation controls of these potential hazards are implemented in the design.

If we think back to the hierarchy, we prefer to fix things in the design, eliminate the hazard if possible, or make changes to the design to eliminate or reduce the hazard, rather than just rely on human beings to catch the problem and deal with it further downstream. It’s far more effective and cheaper, in the long run, to fix things in design they are more effective controls. Certainly, in this standard in Australian law, and in the UK and elsewhere, you will find either regulations or law or codes of practice or recognized and accepted good practice that says, “You should do this”. It’s a very, very common requirement and we should pretty much assume that we have to do this.

Task Description (T204) #5

Interesting clause here in 2.2, it says if no specific hazard analysis techniques are directed or the contractor wants to take a different route to what is directed, then they’ve got to obtain approval from the program manager. If the PM (Project Manager) hasn’t specified analysis techniques, and they may not wish to, they may just wish to say you’ll do whatever analysis is required in order to identify hazards and mitigate them. But in many industries, there are certain ways of doing things and I’ve said before in previous lessons, if you don’t specify that you want something, then contractors will very often cut the safety program to the bone in order to be the cheapest bid. the customer will get what they prioritize. If the customer prioritizes a cheap bid and doesn’t specify what they want, then they will get the bare minimum that the contractor thinks they can get away with. If you don’t ask, you don’t get – Becoming a theme that isn’t it?

Task Description (T204) #6

Let’s move on to 2.3. Returning to software, we’ve got to include that. The software might be developed separately, but nevertheless, the contractor performing the SSHA shall monitor the software development, shall obtain data from each phase of the software development process in order to evaluate the contribution of the software to the subsystem hazard analysis. There’s no excuse for just ignoring the software and treating it as a black box. Of course, very often these days the software is already developed. It’s a GFE or NDI item, but there still should be evidence available or you do a black-box analysis of the subsystem that the software is sitting in. Again, if the software developer reports any identified hazards, they’ve got to be reported to the program manager in order to request appropriate direction.

This assumes a level of interaction between the software developers right up the chain to the program manager. Again, this won’t happen unless the program manager directs it and pays for it. If the PM doesn’t want to pay for it, then they are either going to have to take a risk on not knowing about the functionality of the software that’s hidden within the subsystem. Or they’re going to deal with it some other way, which is often not effective. The PM needs to do a lot of work upfront in order to think what kind of problems there might be associated with a typical subsystem of whatever kind it is we’re dealing with. And think about “How would I deal with the associated risks?” “What’s the best way to deal with them in the circumstances?” If I’m buying stuff off the shelf and I’m not going to get access to hazard analysis or other kinds of evidence, how am I going to deal with them? Big questions.

And then 2.4, the contractor shall update the SSHA following changes, including software design changes. Again, we can’t just ignore those things.  That’s slide six out of six. Let’s move on to reporting.

Reporting (T204) #1

The first slide, contractor’s got to prepare a report that contains results from the task, including within the system description, physical and functional characteristics of the system, a list of the subsystems, and a detailed description of the subsystem being analysed, including its boundaries. And from other videos, you’ll know how much and how often I emphasize knowing where the boundaries are because you can’t really do effective safety analysis and safety management on an unbounded system. It just doesn’t work. There’s a requirement here for quite a lot of information reference to more detailed descriptions as they become available. The standard says they shall be supplied. That’s a lot of information that probably texts and pictures of all sorts of stuff and that’s going to need to go into a report. And typically, we would expect to see a hazard analysis report or a HAR with this kind of information in it. Again, if the PM/customer doesn’t specify that HAR, then they’re not going to get it and they’re not going to get textual information that they need to manage the overall system.

Reporting (T204) #2

So, if we move on to parts B and C of the reporting requirement. We’ve got to describe hazard analysis methods and techniques, provide a description of each method and the technique used, and a description of the assumptions made. And it says for each qualitative or quantitative data. This is another area that often gets missed. If you don’t know what techniques have been used and you don’t know the assumptions that almost certainly that subsystem analyser will have to make because they probably don’t have visibility in the rest of the system. If you don’t have that information, it becomes very difficult to verify the hazard analysis work and to have confidence in it.

And the hazard analysis results. Content and format vary. Something else the PM is going to think about and specify upfront. Then results should be captured the hazard tracking system. Now, usually, this hazard tracking system is hazard log. It might be a database, a spreadsheet or even a word document, or something like that. And usually, in the hazard tracking system, we have the leading particulars. We don’t always have, in fact, we shouldn’t have, every little piece of information in the hazard tracking system because it will quickly become unwieldy. Really, we want the hazard log to have the leading particulars of all the hazards, causes, consequences and controls. And then the hazard log should refer out to that hazard analysis report or other reports and data, whatever they’re called, other records.

If we go back up, this reemphasizes the kind of detail that’s here in 2.5 A. That really shouldn’t be going in the hazard log. That should be going in a separate report which the hazard log/the hazard tracking system refers to. Otherwise, it all gets that unwieldy.

Contracting

I’ve said repeatedly the PM needs to think about this and ask for that.

Contracting; The standard assumes that the information in A to H below is specified way up front in the request for proposal. That’s not always possible to do in full detail, but nevertheless, you’ve got to think about these things really early and include them in the contractual documentation. And again, if your if you’re running a competition, by the time you get to the final RFP, you need to make sure that you’re asking for what you really need. maybe run a preliminary expression of interest or pre-competition exercise in order to tease out, detect. We’ve got to impose task 204 (A.) as a requirement. We may have to specify which people we want to involve, which functional specialists, which discipline specialists (B.). We want to get involved to address this work. Identification of subsystems to be analysed (C.). Well, if you don’t know what the design is upfront, we can’t always do that, but you could say all.

You may specify desired analysis methodologies and techniques (D.). And again, that’s largely domain dependent. We tend to do safety in certain ways in different worlds, in the air world is done in a particular way. in the maritime world, it’s a different way. With Road or Off-Road Vehicle, it’s done in a particular way, etc, etc., whatever it might be. Chemical plant, whatever. If they’re known hazards, hazardous areas or other specific items be examined or excluded (E.) because they’re covered adequately elsewhere. The PM or the client has got to provide technical data on all those non-development developmental items (F.), particularly if they’re specifying that the contractor will use them. If the client says “You will use this. You will use these tires, therefore, this data with these tires” or whatever it might be, you’re going to – we want a system that’s going to use to standardized spares of standardized fuel or whatever it might be or is maintainable by technicians and mechanics with these standard skill sets. There may be all sorts of reasons for asking or forcing contracts to do certain things, in which case the purchaser is responsible for providing that data.

And again, many purchases forget to do that entirely or do it very badly, and then that can cripple a safety program. What’s the concept of operations (G.). What are we going to do with this stuff? What’s the context? What’s the big picture? That’s important. And any other specific requirements (H.). What risk matrix? What risk definitions are we using on this program? Again, important otherwise, different contractors do their own thing, or they do nothing at all. And then the client must pick up pieces afterwards, which is always time-consuming and expensive and painful. And it tends to happen at the back of a program when you’re under time pressure anyway. It’s never a happy place to be. do make sure that clients and purchases that you’ve done your homework and specified this stuff upfront, even if it turns out to be not the best thing you could have specified, it’s better to have an 80 percent solution that’s pretty standard and locked down.

Commentary #1

That’s the wording that’s in the task with some commentary by myself. Now some additional commentary. It says right up front, areas to consider include performance, performance degradation, functional failures, timing errors, design errors or defects and inadvertent function. What we have here basically is a causal analysis, there will be some simple techniques that you can use to identify this kind of stuff. Something like a functional failure analysis or a failure modes effects analysis, which is like an FFA, but an FMEA requires design to work on. And, FMEA, a variant of FME is FMECA, where we include the criticality of the failure as it possibly propagates out the hierarchy of the system.

These sorts of techniques will think about what could go wrong, no function when required, inadvertent function – the subsystem functions when it’s not supposed to – and incorrect function, and there’s often multiple versions of incorrect function. considering all of those causes, all of those failure modes and if we’re doing a big safety program on something quite critical, very often the those identified faults and failures and failure modes will feed into the bottom of a fault tree where we have a hierarchical build-up of causation and we look at how redundancy and mitigation and control measures mitigate those low-level failures and hopefully prevent them from becoming full-blown incidents and accidents.

And these techniques, particularly the FFA in the FMEA, are also good for hazard identification and for investigating performance and non-compliance issues. you can apply an FFA and FMEA those type of techniques to a specification and say “We’ve asked for this. What could happen if we get what we ask for?” What could go wrong? And, what could go wrong with these requirements?

Commentary #2

Now, the second part that I’ve chosen to highlight a consideration of the human within a subsystem and this is important. Traditionally, it’s not always been done that well. Human factors, I’m glad to say is becoming more prominent and more used both because in many, many systems, human is a key component, is a key player in the overall system. And in the past, we have tended to build systems and then just expect the human operator and maintainer to cope with the vicissitudes of that system. maybe the system isn’t that well designed in terms of it is not very usable, its performance depends on being lovingly looked after and tweaked and maybe systems are vulnerable to human error, and even induce human error. We need to get a lot better at designing systems for human use.

So, we could use several techniques. We could use a HAZOP, a hazard analysis operability study to consider information flows to and from the human. There are lots of specialist human factors analyses out there. And I’m hoping to run a series of human factors sessions, interviewing a very knowledgeable colleague of mine but more on that later. that will come in due course. We’ll look at those specialist human analysis techniques. But there’s been a couple of conceptual models around for quite a long time, about 20 years now at least, for how to think about humans in the system.

Human-System Models

So, we’ve got a 5M model and the SHELL model. I’m just going to briefly illustrate those. Now, both models are taken from the US Federal Aviation Authority System Safety Handbook, which dates to the end of 2000. These have been around a long time and they were around before the year 2000, and they’re quite long in the tooth.

We’ve got the SHELL model, which considers our software, hardware, environments and live-ware – the human. And there’s quite a nice checklist on Wikipedia for things to consider. We’re considering all the different interfaces between those different elements. That’s at the hyperlink you can see at the bottom of the slide.

Then on the right-hand side, we’ve got the 5M model and apologies for the gendered language. Where the five Ms are the man/the human, the machine, management, the media – and the media is the environment for operating and maintenance environment – and then in the middle is the mission. the humans, the machines, the systems, and the management come together in order to perform a mission within a certain environment. that’s another very useful way of conceptualizing our contribution of humans and interaction between human and system. Human operators usually are maintainers, frontline staff, and management, all in a particular operating environment and environmental context and how they come together to accomplish the mission or the function of the system, whatever it might be.

Now a word of caution, on this. It’s very possible to spend gigantic sums of money on human analysis. very often we tend to target it at the most critical points and we very often target it at the operator, particularly for those phases of operation where the operator must do things in a limited amount time. the operator will be under pressure and if they don’t take the right action within a certain time, something could go wrong. we do tend to target this analysis in those areas and tend to spend money hopefully in a sensible and targeted way.

Commentary #3

My final slide on the additional commentary. The other things we’ve talked about for this task, compliance checking. We should get a subsystem specification. If we don’t get a subsystem specification, well, what are the expectations on the subsystem? Are they documented anywhere? Is it in the consent to box? Is there an interface requirement document or are there interface control documents for other systems that or subsystems that interface with our subsystem – anywhere where we can get information. if we have a subsystem spec, a bunch of functional requirements say, early on we could do a functional failure analysis of those functional requirements. we can do this work really quite early if we need to and think about, “Well, what interfaces are expected or required from our subsystem?” versus “What is our subsystem actually do?” any mismatches that could give rise to problems.

So, this is a type of activity where we’re looking for continuity and we’re looking for coherence across the interface. And we’re looking for things to join up. And if they don’t join up or they’re mismatched, then there’s a potential problem. And, as we look down into the subsystem, are there any derived safety requirements from above that says this subsystem needs to do this or not do that in order to manage a hazard? Those are important to identify.

Again, if it’s not been done probably the subsystem contractor won’t do it because it’s extra expense. And they may well truly believe that they don’t need to. We’re all proud of the things that we do, and we feel sometimes emotionally threatened if somebody suggests a piece of kit might go wrong and it does blind people to potential problems.

If going the other way, we are a higher-level authority where a system prime contractor or something and we’ve got to look at the documentation from a subsystem supplier. Well, we might find out some information from sales brochures or feature lists, or there might be a description of the benefits or the functions of the system with its outputs. We hopefully should be able to get hold of some operating and maintenance manuals. And very often those manuals will contain warnings and cautions and say, “You must look after the piece of cake by doing this”. I’m thinking the gremlins now “Don’t feed it after midnight or get it wet” otherwise bad things will happen. Sorry about that, slightly fatuous example, but a good illustration, I think. And ideally, if there’s any training materials associated with the piece of kit, is there a training needs analysis that shows how the training was developed? It’s very often in a TNA if it’s done well, there’s lots of good information in there. Even if it’s not quite for the same application that weighs in the piece of kit for, you could learn a lot from that kind of stuff

And finally, if all else fails, if you’ve got a legacy piece of kit, then you can physically inspect it. And if you can take it apart, put it back together again – do so. You might discover there’s asbestos in it. You might discover that lithium batteries or whatever it might be, fire hazards, flammable materials, toxic materials, you name it. there’s a lot of ways that we can get information about the subsystem. Ideally, we ask for everything upfront. Say, you know, if there’s any hazardous chemicals in there, then you must provide the hazard sheets and the hazard data in accordance with international or national standards and so on and so forth. But if you can’t get that or you haven’t asked for it, there are other ways of doing it, but they’re often time-consuming and not the optimal way of doing it.

So again, do think about what you need upfront and do ask for it. And if the contractor can’t supply exactly what you want, what you need, you then have to decide whether you could live with that, whether you could use some of these alternative techniques or whether you just have to say, “No, thanks. I’ll go to another supplier of something similar”. And I may have to pay more for it, but I’ll get a better-quality product that actually comes with some safety evidence that means I can actually integrate it and use it within my system. Sometimes you do have to make some tough decisions and the earlier we do those tough decisions the better, in my experience.

Copyright Statement

So that’s all the technical content. Just to say that all the text that’s in italics and in speech marks is from the standard, which is copyright free. But this presentation, and especially all the commentary and the added value, is copyright at the Safety Artisan 2020.

For More …

And if you want more videos like this, rest in the 882 series and other resources on safety topics, you can find them at the website www.safetyartisan.com. And you can also go to the safety artisan page at Patreon. that’s www.pateron.com and search for Safety Artisan – all one word.

End

So, that’s the end of the presentation and it just remains for me to say, thanks very much for watching and supporting the Safety Artisan. And I’ll be doing Task 205 system hazard analysis next in the series, look forward to seeing you again soon. Bye-bye, everyone.

End: Sub-System Hazard Analysis

You can find a free pdf of the System Safety Engineering Standard, Mil-Std-882E, here.

Categories
Mil-Std-882E Safety Analysis

Preliminary Hazard Analysis

In this 45-minute session, The Safety Artisan looks at Preliminary Hazard Analysis, or PHA, which is Task 202 in Mil-Std-882E. We explore Task 202’s aim, description, scope and contracting requirements. We also provide value-adding commentary and explain the issues with PHA – how to do it well and avoid the pitfalls.

This is the seven-minute-long demo video. The full video is 45 minutes’ long.

Topics: Preliminary Hazard Analysis

  • Task 202 Purpose;
  • Task Description;
  • Recording & Scope;
  • Risk Assessment (Tables I, II & III);
  • Risk Mitigation (order of preference);
  • Contracting; and
  • Commentary.

Transcript: Preliminary Hazard Analysis

Transcript: Preliminary Hazard Analysis

Hello and welcome to the Safety Artisan, where you’ll find professional, pragmatic and impartial safety training resources. So, we’ll get straight on to our session and it is the 8th February 2020. 

Preliminary Hazard Analysis

Now we’re going to talk today about Preliminary Hazard Analysis (PHA). This is Task 202 in Military Standard 882E, which is a system safety engineering standard. It’s very widely used mostly on military equipment, but it does turn up elsewhere.  This standard is of wide interest to people and Task 202 is the second of the analysis tasks. It’s one of the first things that you will do on a systems safety program and therefore one of the most informative. This session forms part of a series of lessons that I’m doing on Mil-Std-882E.

Topics for This Session

What are we going to cover in this session? Quite a lot! The purpose of the task, a task description, recording and scope. How we do risk assessments against Tables 1, 2 and 3. Basically, it is severity, likelihood and the overall risk matrix.  We will talk about all three, about risk mitigation and using the order of preference for risk mitigation, a little bit of contracting and then a short commentary from myself. In fact, I’m providing commentary all the way through. So, let’s crack on.

Task 202 Purpose

The purpose of Task 202, as it says, is to perform and document a preliminary hazard analysis, or PHA for short, to identify hazards, assess the initial risks and identify potential mitigation measures. We’re going to talk about all of that.

Task Description

First, the task description is quite long here. And as you can see, I’ve highlighted some stuff that I particularly want to talk about.

It says “the contractor” [does this or that], but it doesn’t really matter who is doing the analysis, and actually, the customer needs to do some to inform themselves, otherwise they won’t really understand what they’re doing.  Whoever does it needs to perform and document PHA. It’s about determining initial risk assessments. There’s going to be more work, more detailed work done later. But for now, we’re doing an initial risk assessment of identified hazards. And those hazards will be associated with the design or the functions that we’re proposing to introduce. That’s very important. We don’t need a design to do this. We can get in early when we have user requirements, functional requirements, that kind of thing.

Doing this work will help us make better requirements for the system. So, we need to evaluate those hazards for severity and probability. It says based on the best available data. And of course, early in a program, that’s another big issue. We’ll talk about that more later. It says including mishap data as well, if accessible: American term mishap, it means accident, but we’re avoiding any kind of suggestion about whether it is accidental or deliberate.  It might be stupidity, deliberate, whatever. It’s a mishap. It’s an undesirable event. We look for accessible data from similar systems, legacy systems and other lessons learned. I’ve talked about that a little bit in Task 201 lesson about that, and there’s more on that today under commentary. We need to look at provisions, alternatives, meaning design provisions and design alternatives in order to reduce risks and adding mitigation measures to eliminate hazards. If we can all reduce associated risk, we need to include all of that. What’s the task description? That’s a good overview of the task and what we need to talk about.

Reading & Scope

First, recording and scope, as always, with these tasks, we’ve got to document the results of the PHA in a hazard tracking system. Now, a word on terminology; we might call hazard tracking system; we might call it hazard log; we might call it a risk register. It doesn’t really matter what it’s called. The key point is it’s a tracking system. It’s a live document, as people say, it’s a spreadsheet or a database, something like that. It’s something relatively easy to update and change. And, we can track changes through the safety program once we do more analysis because things will change. We should expect to get some results and to refine them and change them as time goes on. Very important point.

Scope #1

Scope. Big section this. Let me just check. Yes, we’ve got three slides on scope. This does go on and on. The scope of the PHA is to consider the potential contribution from a lot of different areas. We might be considering a whole system or a subsystem, depending on how complex the thing is we’re dealing with. And we’re going to consider mishaps, the accidents and incidents, near misses, whatever might occur from components of the system (a. System components), energy sources (b. Energy sources), ordnance (c. Ordnance)- well that’s bullets and explosives to you and me, rockets and that kind of stuff.

Hazardous materials (d. Hazardous Materials (HAZMAT)), interfaces and controls (3. Interfaces and controls), interface considerations to other systems (f. Interface considerations to other systems when in a network or System-of-Systems (SoS) architecture), external systems. Maybe you’ve got a network of different systems talking to each other. Sometimes that’s called a system of systems architecture. Don’t worry about the definitions. Our system probably interacts and talks to other systems, or It relies on other systems in some way, or other systems rely on it. There are external interfaces. That’s the point.

Scope #2

We might think about material compatibilities (g. Material Compatibilities) – Different materials and chemicals are not compatible with others-, inadvertent activation (h. Inadvertent activation).

Now, I’ve highlighted I. (Commercial-Off-the-Shelf (COTS), Government-Off-the-Shelf (GOTS), Non-Developmental Items (NDIs), and Government-Furnished Equipment (GFE).) because it’s something that often gets neglected. We also need to think about stuff that’s already been developed. The general term is NDIs and it might be commercial off the shelf, it might be a government off the shelf system, or government-furnished equipment  GFE- doesn’t really matter what it is. These days, especially, very few complex systems are developed purely from scratch. We try and reuse stuff wherever we can in order to keep costs down and schedule down.

We’re going to need to integrate all these things and consider how they contribute to the overall risk picture. And as I say, that’s not often done well. Well, it’s hardly ever done well. It’s often not done at all. But it needs to be, even if only crudely. That’s better than nothing.

J. (j. Software, including software developed by other contractors or sources.  Design criteria to control safety-significant software commands and responses (e.g., inadvertent command, failure to command, untimely command or responses, and inappropriate magnitude) shall be identified, and appropriate action shall be taken to incorporate these into the software (and related hardware) specifications)  we need to include software, including software developed elsewhere. Again, that’s very difficult, often not done well. Software is intangible. If somebody else has developed it maybe we don’t have the rights to see the design, or code, or anything like that. Effectively it’s a black box to us. We need to look at software. I’m not going to bother going through all the blurb there.

Another big thing in part k (k.  Operating environment and constraints) is we need to look at the operating environment. Because a piece of kit that behaves in a certain way in one environment, you put it in a different environment and it behaves differently. And it might become much more dangerous. You never know. And the constraints that we put under on system. Operating environment is very big. And in fact, if you see the lesson I did on the definition of safety, we can’t really define whether a system is safe or not until we define the operating environment. It’s that important, a big point there.

Scope #3

And then third slide of three procedures (l. Procedures for operating, test, maintenance, built-in-test, diagnostics, emergencies, explosive ordnance render-safe and emergency disposal). Again, these are well these often don’t appear until later unless of course, we’ve gone off the shelf system. But if we have got off the shelf system; there should be a user manual, there should be maintenance manuals, there should be warnings and cautions, all this kind of stuff. So, we should be looking for procedures for all these things to see what we could learn from them. We want to think about the different modes (m. Modes) of operation of the system. We want to think about health hazards (n. Health hazards) to people, environmental impacts (o. Environmental Impacts), because they take to includes environmental.

We need to think about human factors, human engineering and human error analysis (p. Human factors engineering and human error analysis of operator functions, tasks, and requirements). And it says operator function tasks and requirements, but there’s also maintenance and disposal of storage. All the good stuff. Again, Human Factors is another big issue. Again, it’s not often done well, but actually, if you get a human factor specialist statement early, you can do a lot of good work and save yourself a lot of money, and time, and aggravation by thinking about things early on.

We need to think about life support requirements (q.  Life support requirements and safety implications in manned systems, including crash safety, egress, rescue, survival, and salvage). If the system is crewed or staffed in some way, I’m thinking about, well, ‘What happens if it crashes?’ ‘How do we get out?’ ‘How do we rescue people?’ ‘How do we survive?’ ‘How do we salvage the system?’

 Event-unique hazards (r. Event-unique hazards). Well, that’s kind of a capsule for your system does something unusual. If it does something unusual you need to think about it.

And then thinking about part s. infrastructure (s.  Built infrastructure, real property installed equipment, and support equipment), property installed equipment and support equipment in property and infrastructure.

And then malfunctions (t. Malfunctions of the SoS, system, subsystems, components, or software) of all the above.

I’m just going to whizz back and forth. We’ve got to sub-item T there. We’ve got an awful lot of stuff there to consider. Now, of course, this is kind of a hazard checklist, isn’t it? It’s sort of a checklist of things. We need to look at all that stuff. And in that respect, that’s excellent, and we should aim to do something on all of them just to see if they’re relevant or not if nothing else. The mistake people often make is because they can’t do something perfect and comprehensive, they don’t do anything. We’ve got a lot of things to go through here. And it’s much better to have a go at all these things early and do a bit of rough work in order to learn some stuff about our system. It’s much better to do that than to do nothing at all. And with all of these things, it may be difficult to do some of these things, the software, the COTS, things where we don’t have access to all the information, but it’s better to do a little bit of work early than to do nothing at all waiting for the day to arrive when we’ll be able to do it perfectly with only information. Because guess what? That day never comes! Get in and have a go at everything early, even if it’s only to say, ‘I know nothing about this subject, and we need to investigate it.’ That’s the pros and cons of this approach. Ideally, we need to do all these things, but it can be difficult.

Risk Assessment

Moving on. Well, we’ve looked to a broad scope of things for all the hazards that we identify and there are various techniques you can use. The PHA has go to include a risk assessment. That means that we’ve got to think about likelihood and severity and then that gives us an overall picture of risk when we combine the two together. That’s tables 1 and 2.

And then, forget risk assessment codes I’m not sure why that’s in there, table 3 is the risk matrix and 88 2 has a standard risk matrix. And it says use that unless you’ve got a tailored matrix for your system that’s been approved for use. And in this case, it says approved effectively in accordance with the US Department of Defence. But it’s whoever is the acquiring organization, the authority, the customer, the purchaser, whatever you want to call it, the end-user. We’ll talk about that more in a sec.

Table I, Severity

Let’s start by looking at severity, which in many ways is the easiest thing to look at. Now, here we’ve got in this standard we’ve got an approach based on harm to people, harm to the environment, and monetary loss due to smashing stuff up. At the top catastrophic accident. Category 1 is a fatal accident. This accident could result in death, permanent total disability, irreversible significant environmental impact, or monetary loss. And in this case, it says $10 million. Well, this, that’s 10 million US dollars. This standard was created in 2012, this version of the standard, probably inflation has had an effect since then. And a critical accident, we could cause partial disability injuries or occupational illness that can hospitalized three people are reversible. Significant environmental impact or some losses between 1 million and 10. And then we go down to marginal. Injury or hospital, lost workdays for one person, reversible moderate environmental impact or monetary loss between $100,000 and one million dollars. And then finally negligible is less than that. Negligible is an injury or illness that doesn’t result in any lost time at work, minimal environmental impact, or a monetary loss of less than a hundred thousand dollars. That’s easy to do in this standard. We just say, ‘What are our losses that we think could result?’ Worst case, reasonable scenario or an accident? That’s straightforward.

Table II, Probability

Now let’s look at probability. We’ve got a range here from ‘a’ to ‘e’, frequent down to improbable, and then F is eliminated. And eliminated in the standard really does mean eliminated. It cannot happen ever! It does not mean that we managed to massage the figures, the likelihood a probability figures, down Low that we pretend that it will never happen. It means that it is a physical impossibility. Please take note because I’ve seen a lot of abuse of that approach. That’s bad practices to massage the figures down to a level where you say, ’I don’t need to bother thinking about this at all!’ because the temptation is just to frig [massage] the figures and not really consider stuff that needs to be considered. Well, I’ll get off my soapbox now.

Let’s go back to the top. Frequent- you’ve said, for one item, likely to occur often. Down to probable- occur several times in the life of an item. Occasional- likely to occur sometimes, we think it’ll happen once in the life of an item. Remote- we don’t think it’ll happen at all, but it could do. And improbable – so unlikely for an individual item that we might assume that the occurrence won’t happen at all. But when we consider a fleet, particularly, I’ve got hundreds or thousands of items, the cumulative risk or cumulative probability, sorry, I should say, is unlikely to occur across the fleet, but it could.

And this is where this specific vs. fleet occurrence or probability is useful. For example, if we think ‘Let’s imagine a frequent hazard’. We think that something could happen to an item, per item, let’s say once a year. Now, if we’ve got a fleet of fifty of these items or fifty-something of these items, that means it’s going to happen across the fleet pretty much every week on average. That’s the difference. And sometimes it’s helpful to think about an individual system. And sometimes it’s helpful to think about a fleet where you can you’ve got relevant experience to say, ‘Well the fleet that we’re replacing. We had a fleet of 100 of these things. And we at this go, this went wrong every week or every month or once a year or only happened once every 10 years across the entire fleet.’ And therefore, we could reason about it that way.

We’ve got two different ways of looking at probability here. And use whichever one is more useful or helps you. But when we’re doing that, try and do that with historical data, not just subjective judgment. Because otherwise your subjective judgment, one individual might say ‘That will never happen!’, whereas another will say, ‘Well, actually we experienced it every month on our fleet!’. Circumstances are different.

Table III, Risk Matrix

We put severity and probability together. We have got 1 to 4 on severity, A to F on probability, and we get this matrix. We’ve got probability down the side and severity along the top. And in this standard, we’ve got high risk, serious risk, medium risk and low risk. And now how exactly you define these things is, of course, somewhat arbitrary. We’ll just look at some general principles.

The good thing about this risk matrix is- First, the thing to remember is that risk is the product of probability and severity. Effectively we multiply the two together and we go, well, if we’ve got a catastrophic or a critical risk. And it’s if we’ve got a more serious risk and it’s going to happen often that’s a big risk. That’s a that’s a high risk. Where alternatively, if we’ve got a low severity accident that we think will happen very, very rarely, then that’s a low risk. That’s great.

One thing to note here it’s easier to estimate the severity than it is the probability. It’s quite easy to under- or overestimate probability. Usually, because of the physical mechanism involved, it’s easier to estimate the severity correctly. If we look on the right-hand side, at negligible. We can see that if we’re confident that something is negligible, then it can be a low risk. But at the very most, it can only be a medium risk. We are effectively prioritizing negligible severity risks quite low down the pecking order.

Now, on the other side, if we think we’ve got a risk that could be catastrophic, we could kill somebody or do irreversible environmental damage, then, however improbable we think it is, it’s never going to be classified less than medium. That’s a good point to note. This matrix has been designed well, in the sense that all catastrophic and critical risks are never going to get the low medium and they can quite easily become serious or high. That means they’re going to get serious management attention. When you put risks up in front of a manager, senior person, a decision-maker, who’s responsible and they see red and orange, they’re going to get uncomfortable and they’re going to want to know all about that stuff. And they will want to be confident that we’ve understood the risk correctly and it’s as low as we can get it. This matrix is designed to get attention and to focus attention where it is needed.

And in this standard, in 88, you ultimately determine whether you can accept risk based on this risk rating. In 882, there is no unacceptable, intolerable risk. You can accept anything if you can persuade the right person with the right amount of authority to sign it off. And the higher the risk, the higher the level of authority you must get in order to accept the risk and expose people to it. This matrix is very important because it prioritizes attention. It prioritizes how much time and effort money gets spent on reducing risks. You will use it to rank things all the time and it also prioritizes, as we’ll see later, how often you review a risk because clearly, you don’t want to have high risks or serious risks. Those are going to get reviewed more often than a medium risk or low risk. A low risk might just get review routinely, not very often, maybe once a year or even less. We want to concentrate effort and attention on high risks and this matrix helps us to do that. But of course, no matrix is perfect.

Now, if we go back. Looking at the yellow highlight, we’re going to use table three unless there’s a tailored alternative definition, a tailored alternative matrix. Now, noting this matrix, catastrophic risk, the highest possible risk, we’ve got one death. Now, if we had a system where it was feasible to kill more than one person in an accident, then really, we would need another column worse than catastrophic. We could imagine that if you had a vehicle that had one person in it and the vehicle crashed, whatever it was, a motorbike let’s say. Let’s imagine you only said ‘We’re only going to have solo riders. We can only kill one person.’. We’re assuming we won’t hurt anybody else. But if you’ve got a car where you’ve got four or more people in, you could kill several people. If you’ve got a coach or a bus, you could drive it off a cliff and kill everybody, or you might have a fire and some people die, but most of them get out. You can see that for some vehicles, for some systems, you would need additional columns. Killing one person isn’t the worst conceivable accident.

Some systems. You might imagine quite easily, say with a ship, it’s actually very rare for a ship to sink and everybody dies. But it’s quite common for individuals on ships to die in health and safety type accidents, workplace accidents. In fact, being a merchant seaman is quite a risky occupation. But also in between those two, it’s also quite possible to have a fire or asphyxiating gases in a compartment. You can kill more than one person, but you won’t kill the entire ship’s company. Straight away in a ship, you can see there are three classes, if you like, of serious accidents where you can kill people. And we knew we should really differentiate between the three when we’re thinking about risk management. And this matrix doesn’t allow you to do that. If you’ve got a system where more than one death this is feasible, then this matrix isn’t necessarily going to serve well, because all of those type of accidents get shoved over into a catastrophic column, on this matrix, and you don’t differentiate between any of between them which is not helpful. You may need to tailor your matrix and add further columns.

And depending on the system, you might want to change the way that those risks are distributed. Because you might have a system, for example riding a bicycle. It’s very common riding a bicycle to get negligible type injuries. You know you fall off, cuts and bruises, that kind of thing. But, if you’re not on the road, let’s say you’re riding off-road it is quite rare to get utilities unless you do a mountain biking on some extreme environment. You’ve got to tailor the matrix for what you’re doing. I think we’ve talked about that enough. We’ll come back to that in later lessons, I’m sure.

Risk Mitigation

Risk mitigation, we’re doing this analysis, not for the sake of it, we’re doing it because we want to do something about it. We want to reduce the risk or eliminate it if we can. 88 2 standard gives us an order of precedence, and as it says it’s specified in section 4.3.4, but I’ve reproduced that here for convenience. Ideally, we would like to eliminate hazards by designing them. We would make a design decision to say, ‘We will- we won’t have a petrol engine, let’s say, in this vehicle or vessel because petrol a serious fire explosion hazard. We’ll have something else. We’ll have diesel or we’ll have an all-electric vehicle maybe these days or something like that.’ We can eliminate the risk.

We could reduce the risk by altering the design introducing sort of failsafe features, or making the design crashworthy, or whatever it might be. We could add engineered features or devices to reduce risk safety features seatbelts in cars or airbags, roll balls, crash survivable cages around the people, whatever it might be. We can provide warning devices to say ‘Something’s going wrong here, and you need to pull over’ or whatever it is you need to do. ‘Watch out!’ because the system is failing and maybe ‘Your brakes are failing. You’ve got low brake fluid. Time to pull over now before it gets worse!’.

And then finally, the least effective precautions or mitigations signage, warning signs – because nobody reads warning signs, sadly. Procedures. Good, if they’re followed. Again, very often people don’t follow them. They cut corners. We train people. Again, they don’t always listen to the training or carry it out. And we provide PPE. That’s personal protective equipment. And again, PPE is great if you enforce it. For example, I live in Australia. If you cycle in Australia, if you ride a bicycle, it’s the law that you wear a bike helmet. Most people obey the law because they don’t want to get a $300 fine or whatever it is if the cops catch you, but you still see people around who don’t wear one. Presumably, because they think they’re bulletproof, and it will never happen to them. PPE is fine if it’s useful. But of course, sometimes PPE can make a job that much harder that people discard it. We really need to think about designing a job to make it easy to do, if we’re going to ask people to wear awkward PPE. Also, by the way, we need to not ask them to wear PPE for trivial reasons just so that the managers can cover their backsides. If you ask people to wear PPE when they’re doing trivial jobs where they don’t need it then it brings the system into disrepute. And then people end up not wearing PPE for jobs where they really should be wearing it. You can over-specify safety and lose goodwill amongst your workers if you’re not careful.

Now those risk mitigation priorities, that’s the one in this standard, but you will see an order of precedence like that in many different countries in the law. It’s the law in Australia. It’s the law in the UK, for example, expressed slightly differently. It’s in lots of different standards for good reason because we want to design out the risks. We want to reduce them in the design because that’s more effective than trying to bolt on or stick home safety afterwards. And that’s another reason why we want to get in early in a project and think about our hazards and our risks early on. Because it’s cheaper at an early stage to say, ‘We will insist on certain things in the design. We will change the requirements to favour a design that is inherently safe.’

Contracting

We only get these things if we contract for them. The model in 88 2, the assumption is it’s a government somewhere contracting a contractor to do stuff. But it doesn’t have to be a government, it can be any client or purchase of world authority or end-user asking for something, buying something, contracting something, be it the physical system, or service, or whatever it might be. The assumption is that the client issues a request for proposal.

Right at the start, they say ‘I want a gizmo’. Or ‘I want- I don’t even want to specify that I want a gizmo. I want something that will do this job. I don’t care what it is. Give me something that will do this job.’ But even at that early stage, we should be asking for preliminary hazard analysis (PHA) to be done. We should be saying, ‘Well, who?’ ‘Which specialists?’ ‘Which functional disciplines need to be involved?’. We need to specify the data that we require and the format that it’s in. Considering, especially the tracking system, which is task 106. If we’re going to get data from lots of different people, best we get it in a standardized format we can put it all together. We want to insist that they identify hazards, hazardous locations, etc. We want to insist on getting technical data on non-developmental items, either getting it for the client or the client supplies it. Says to the contractor or doing it ‘This is the information that I’m going to supply you’ and you will use it. We need to supply the concept of operations and of course, the operating environment. Let me just check, no that that’s it. We’ve only got one slide on commentary. It doesn’t say the environment, but we do need to specify that as well, and hopefully that should be in the concept of operations, and a specific hazard management requirement. For example, what matrix are we going to use? What is a suitable matrix to use for this system?

Now to do all of this, the purchaser, the client really probably needs to have done Task 202 and 201 themselves, and they’ve done some thinking about all of this in order to say, ‘With this system, we can envisage- with this kind of requirement, we can envisage these risks might be applicable.’ And ‘We think that the risks might be large or small’ depending on what the system is or ‘We think that-’. Let’s say if you if you purchase a jet fighter, jet fighters because of that demand, the overwhelming demand for performance, they tend to be a bit riskier than airliners. They fall out of the sky more often. But the advantages, there’s normally only one or two people on board. And jet fighters tend to fly a lot of the time in the middle of nowhere. You’re likely to hurt relatively few people, but it happens more often.

Whereas if you’re buying an airliner something, you can shove a couple of hundred people in at one go, those fall out of the sky much less frequently, thank goodness, but when they do, lots of people get hurt. Aa different approach to risk might be appropriate for different types of system. And when your, you should be thinking about early on, if you’re the client, if you’re the purchaser. You should have done some analysis to enable you to write a good request for proposal, because if you write a bad request for proposal, it’s very difficult to recover the situation afterwards because you start at a disadvantage. And the only way often to fix it is to reissue the RFP and start again. And of course, nobody wants to do that because it’s expensive and it wastes a lot of time. And it’s very embarrassing. It is a career-limiting thing to do, a lot of people. You do need to do some work up front in order to get your RFP correct. That’s what it says in the standard.

Commentary

I want to add a couple of comments, I’m not going to say the much. First, it’s a little line from a poem by Kipling that I find very, very helpful. And Kipling used to be a journalist and it was it was his job to go out and find out what the story was and report it. And to do that he used his six honest serving men. He asked ‘What?’ and ‘Why?’ and “When?’ and ‘Who?’, sorry, and ‘How?’ and ‘Where?’ and ‘Who?’. Those are all good questions to ask. If you can ask all those questions and get definite answers, you’re doing well. And a little tip here as a consultant, I rock up and one of the tricks of the trade I use is I turn up as the ‘dumb consultant’ – I always pretend to be a bit dumber than what I really are- and I ask these stupid questions. And I ask the same questions of several different people. And if I get the same answer to the same question from everyone, I’m happy. But that doesn’t always happen. If you start getting very different answers to the same question from different people, then you think, ‘Okay, I need to do some more digging here’. And it’s the same with hazard analysis. Ask the what, why, when, where and who question.

Another issue, of course, is ‘How much?’ ‘How much is this going to take?’ ‘How long is this going to take?’ ‘How many people am I going to have to invite to this meeting?’, etc. And that’s difficult. And really, the only way to answer these questions properly is to just do some PHI and PHA early and to learn from the results. The other alternative, which we are really good as human beings, is to ask the questions early to get answers that we don’t really like and then just to sweep them under the carpet and not ask those questions ever again because we’re frightened of the answers that we might. However frightened you are of the answer, you might get do ask the question because forewarned is forearmed. And if you know about a problem, you can do something about it. Even if that something is to rewrite your CV and start looking for another job. Do ask the questions even if it makes people uncomfortable. And I guess learning how to ask the questions without making people uncomfortable is one of the tricks that we must learn as safety engineers and consultants. And that’s an important part of the job. The soft skills really that you can only learn through practice, really, and observing people.

What’s the way to do it? Well, I’ve said this several times but do your PHI and PHA early. Do it as early as possible because it’s cheap to do it early. If you’re the only safety person or safety, you often in the beginning, maybe you’re a manager, maybe safety is part of your portfolio, you’ve got other responsibilities as well. Just sit down one day and ask these dumb questions, go through the checklist in Task 202 and say, ‘Do I have these things in my system?’

If you know for sure you’re not going to have explosive ordnance, or radiation, or whatever it might be, you can go, ‘Great. I can cross those off the list’. I can make an assumption or I can put a constraint in, by the way, if you really want to do it well and say ‘We will have no explosive devices’, ‘We will have no energetic materials.’, ‘We will have no radiation’ or whatever it might be. Make sure that you insist that you’ll have none of it then you can hopefully move on and never have to deal with those issues again.

Do the analysis early, but expect to repeat it because things change, and you learn more and more information comes in. But of course, the further you go down the project, the more expensive everything gets. Now, having said do it, do it early, the Catch 22 is very often people think ‘How can I analyse when I don’t have a design?’

The catch 22 question is what comes first, design or analysis? Now, the truth is that you could do analysis on very simple functions. You don’t need any design at all. You don’t even need to know what kind of vehicle or what kind of system you might dealing with. But of course, that will only take you so far. And it may be that you want to do early analysis, but for whatever reason, [Intellectual Property Rights] IPR or whatever it might be, you can’t get access to data.

What do you do? You can’t get access to data about your system or the system that you’re replacing. What do you do? Well, one of the things you can do is you can borrow an idea from the logistics people. Logistic support analysis Task 203 is a baseline comparison system. Imagine that you’re going to have a new system, maybe is replacing an old system, but maybe it does a lot more than the old system used to do. Just looking at the old system isn’t going to give you the full picture. Maybe what you need to do is make up an imaginary comparison system. You take the old system and say, ‘Well, I’m adding all this extra functionality’. Maybe the old system, we just bought the vehicle. We didn’t buy the support system, we didn’t buy the weapons, we didn’t buy the training, whatever it might be. But, this time round, we’re buying the complete package. We’re going to have all this extra stuff that probably has hazards associated with it, but just doing lessons learned from the previous system will not be enough.

Maybe you need to construct an imaginary Baseline Comparison System and go, ‘I’ll borrow bits from all these other systems, put them all together, and then try and learn from that sort of composite system that I’ve invented, even though it’s imaginary.’ That can be a very powerful technique. You may get told, ‘Oh, we haven’t got the money’ or ‘We haven’t got the time to do that’. But to be honest, if there’s no other way of doing effective, early analysis, then spend the money and do it early. Because many times I’ve seen people go, ‘Oh, we haven’t got time to do that’. They’ve never got time to do it properly and therefore, you end up doing it. You go around the buoy two or three times. You do it badly. You do it again slightly less badly. You do it a third time. And it’s sort of barely adequate. And then you move forward. Well, you’ve wasted an awful lot of time and money and held up other people, the rest of the project doing that. Probably it’s better off to spend the money and just get on with it. And then you’re informed going forwards before you start to spend serious money elsewhere on the project.

Copyright Statement

Well, that’s it for me. Just one thing to say, that Mil. Standard 882E came out in 2012. Still going strong, unlikely to be replaced anytime soon. It’s copyright free. All the quotations are from the standard, they’re copyright free. But this video is copyright of The Safety Artisan 2020.

For More …

And you can find a lot more information, a lot more safety videos, at The Safety Artisan page at www.Patreon.com and you can find more resources at www.safetyartisan.com.

End

That is the end of the show. Thank you very much for listening. And it just remains for me to say. Come and watch some more videos on Mill-Std-882E. There’s going to be a complete course on them, and you should be able to get, I hope, a lot of value out of the course. So, until I see you again, cheers.

End: Preliminary Hazard Analysis

You can find a free pdf of the System Safety Engineering Standard, Mil-Std-882E, here.