"Human Error" or "Diver Error": Are they just an easy way of blaming the individual?

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GLOC

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Copied from the original site linked at the bottom

Human error is normal. Human error is part of the way we learn. It is almost impossible to remove human error from any system. Therefore, 'Human error' should not be the conclusion of an investigation. If it is, then we are not likely to improve the situation for the future. Depending on the outcome of the error or errors, the impact can be minor or it can be fatal, the problem is we don't necessarily know the scale of the issue until after the event.

In the last blog I covered the basic concept of a Just Culture and why it is essential to have this if we are to improving safety. We need to be able to talk about the errors or violations (at risk behaviours) that occur, and the reasons why it made sense to us at the time if we are to improve performance and safety, and reduce the likelihood of the same adverse event happening again. In this blog I am going to talk about 'human error' and the differences that exist within this overly-simple classification. The next two blogs will cover 'Risk behvaiours' and 'Reckless behaviours' which sit on the right-hand side of this model.

Human Error

Human Error can be defined as “the failure of a planned action to be completed as intended, or the use of a wrong plan to achieve an aim. Errors can include problems in practice, products, procedures, and systems.”. This could be as simple as picking up the wrong keys, driving past the turn-off on the way to a friends house, picking up strawberry jam instead of raspberry, or in the context of diving, forgetting to write the correct gas analysis on the tape, miscalculating a maximum operating depth or turn pressure, running out of gas or losing our buddy.

We all make errors every day with generally minimal consequences. In aviation, research has shown pilots make in the order of 3-6 errors per hour and yet they still don't crash that often - fortunately! In diving the errors we make also have the potential for dire consequences. Again, fortunately many errors are picked up by the diver before it becomes too late. However, sometimes we get distracted, or miss the clues and cues which would identify the problem developing. Clues and cues which are easily identifiable after the event because we are working backwards joining the dots rather than trying to create a dynamic jigsaw puzzle without all the pieces or knowing where it will end.

The following diagrams show this. The first is a very simple linear decision treee which leads to an adverse outcome. The decisions made are shaped by those factors in Situational Awareness model from previous blogs. By the time we get to the adverse outcome, there are 27 possible outcomes. (It is recognised that in the real world we have mulitple parallel and serial decision making processes happening at the same time and therefore life is far more complicated than this!!)

Pof403W1TNm3hz01zacC_Outbound.png


The second diagram starts from the outcome and works backwards.

P3bBaqVSmmlh8XXDcwSc_Inbound.png




Most people when looking at an incident look for clues and cues to back up our hypothesis knowing what happened. e.g. the diver ran out gas, that's because they weren't monitoring their consumption, because they were poorly trained...but the evidence as you move further back down the path gets weaker. It is easy to blame the indivudual and tell them "remember to monitor your gas" - that is like saying "don't walk on the motorway because you'll get hit by a car". However, in the latter case, the risks are more easily recalled and so the warning is more likely to be adhered to. Evidence showing the number of divers running out of gas, but still surviving is really poor yet out of gas is the most common trigger for fatalities according to DAN.

For instructors there is an increased level of pressure not to make a mistake. They are expected to be somehow ‘above’ human fallibility and not make mistakes. We need to understand that individuals, instructors and non-instructors alike, do not intend the mistake or error or undesirable outcome even though the consequences are potentially life threatening. Many discussions use phrases such as 'why did they make the choice' or 'they made an error' which infers that a choice was actively made. However, as we have seen in these two blogs (here and here), many of the decisions we make are subconscious and therefore there is no active choice.

I sometimes get asked about how to deal with individuals who make repeated errors. First off we need to understand the type of errors that are being made. Are the errors due to lack of skill, knowledge or training, or is it because they are in an error prone environment such as a busy filling station with lots of pressure to mix different fills against the clock, or a dive centre which pays their instructor 'per student' and time is the limiting factor? Has the equipment been designed to reduce error, or is it known that there are workarounds to get the job done due to poor design? Are the individuals stressed, distracted or unfocussed, all of which will lead to a greater likelihood of an error occuring. Furthermore, once someone has made an error in an environment where errors aren't tolerated (losing their job or critical outcome), they are likely to be more stressed. Therefore we first must understand the system aspects of the adverse event before we can determine the best way forward.
 
How to deal with Human Error?

Firstly, understand the situation and try to understand why it made sense to the individual (or you) at the time. For example, an instructor is a position of authority and acts as a role model. If that instructor does not analyse their gas all week on a training class like in this incident (despite standards saying they must do), and the student ended up diving with 72% rather than air, then it is no wonder that the students didn't analyse their gas. Or why the AOW diver carried on diving in unsafe situations because they felt an obligation to their instructor.

  • If time is a pressure, then get ready earlier.
  • If confusion often happens within the team, make a more comprehensive brief ensure there is clear role clarity.
  • If things keep getting forgotten, make a list and get into the habit of using it.
  • If buddies keep swimming off and you end up diving solo, find out why? Is it your attention or theirs which is lacking. Do you have contradictory dive goals? Macro photography versus wreck exploration?
Secondly, if you are the subject of the human error, write down what happened and what led to the incident, not just the actions and outcomes but why you made the decisions you did, what pressures you were under, what the goals of the dive were and so on. It is by understanding the motivations (see bottom of Endsley's model) that we can have a better chance of improving safety and performance. Talk through the event with others who were involved. And then submit a report to the Diving Incident Safety Management System (DISMS), an online confidential reporting system or similar. Feel free to drop me a line too if you want someone to talk to. I am very approachable and every said will be confidential in nature.

Thirdly, if you are in a position of authority or hold a supervisory role, consider that if the outcome is really bad, there might be second victim issues at hand whereby those involved feel guilty for what happened, because they feel they were unable to stop the situation from developing.

Finally, if you are involved in an adverse event investigation and the summary is "Diver Error" or "Human Error" then start looking deeper. Those terms should be used as a starting point for a more detailed investigation, not the final conclusion.

Next Blog

The next blog will look at 'at risk behaviours' which covers those areas normally known as violations. They blended area in the FAIR model in the previous blog. It is easy to classifiy something as a violation, especially when there are rules in place, but sometimes the context needs to be understood to see if the motivation for breaking the rules was for personal or organisational gain, or whether the rules are not applicable or workable.



Footnote:

The Human Factors Academy provides two classes to improve human performance and reduce the likelihood of human error of occuring. The online class provides a comprehensive grounding of Human Factors giving you the basic skills need to improve human performance and reduce errror, whereas the classroom-based class is very comprehensive and intense with plenty of opportunity to learn from failure and error, providing an opportunity to be reflective on behaviours and performance.

More information on Human Factors Skills in Diving classes can be found at www.humanfactors.academy

Upcoming classroom-based course dates are here Training Dates

Online micro-class (9 modules of approximately 15 mins each) details are here Human Factors Skills in Diving Online Mini-Course
 
interesting article well done, for me it reemphasises the need for a buddy /self check in your first diagram of adverse outcome the experience and traning of your buddy goes along way in short circuiting the adverse outcome position, not always achievable in an instructor /student role. looking back over my AOW course I reflect on a potentially serious situation i was in where 4 fellow divers did NOT notice my dump valve was leaking. One would hope that as diving experience is gained that your buddy would be your second set of eyes or to put it in context would be a sort of trip switch that stops you reaching the adverse outcome position
 
Hi Lermontov,

Thanks for the feedback. Nice to know people are reading the posts :)

The diagrams are conceptual in nature and can be applied to individual or team environments. The point being made however is that often we make decisions based on maybe one or two levels ahead. Think about chess players who think one or two moves ahead and Grand Masters who play 8-10 moves ahead. There is a limit to the permutations we can capture, but that is what experts do.

Each team member will have their own SA and only when that SA is overlapping does team SA occur. This is why it is so important to set out the goals/plan the dive as that influences where SA and Decision Making are focused. The SA model from Endsley shows this clearly.

In an instructor / student role, the instructor is part of the team and the students should contribute to that SA too. Too often though, students are afraid of speaking up when they see something not quite right. We need to create that environment where they can speak up, they may have that critical piece of information but not necessarily understand its significance.
 
Its very difficult to quantify/measure SA - Im a believer in the mentor model for training over the text book style of accumulated knowledge. If we place a graph of time/risk ( or lack of SA that places us in danger) then clearly a beginner diver is at the higher risk status over a more experienced diver., although the factors come into play to sideswipe us eg complacency etc I agree with your last paragraph that also applies to any diver combination, the big disadvantage is that onsite communication is not easy without some sort commercial dive mask. Ideally what they want is fro the mentor to be able to verbalise the thought process as they dive so that the students global awareness is enlarged e.g. what depth are we,, how long do we have NDL, how much gas, if i go into deco whats my RMV at 6m, if it silts up can i escape , whats the plan if we get separated in an overhead etc etc all those though process are internal and automatic for an experienced diver, some are predive discussions but often the situation needs adjustment as we foresee a situation ahead ( like your tree branches)

I liken it to Health and Safety the anticipation of adverse situations is a different way of looking at the (dive) environment mostly learned through time on the job, I'm not convinced everyone can conceptualise the situation that were talking about. It seems to be self regulating those that can do and those that cant will find their own threshold of risk and stay inside that boundary.
This is a huge but important topic and In my view SA is a thought process that evolves with finer and more subtle detail as we continue to dive
 
Anything not equipment failure is diver error IMO. If you run out of air, get tangled in line or net, get swept away by current, get lost, and any one of a myriad of other ways to die - you either weren't paying attention or weren't prepared.

I had a 2nd dive on Roatan where the 1st dive was changed and the boat moved after splashing. The DM signaled us to hold and went up to tell the boat to move and then led us in a different direction. 2nd dive, in even stronger current, I got to the meeting place and all had left - the DM left me behind. I could have tried to catch up but didn't know if the plan had changed like the 1st dive.

If I had tried to catch up and the boat left would it have been any fault other than mine alone? I think not. I went back to the boat and sat the dive out. I could have taken the chance and tried to save the dive BUT if the boat had moved I would surely have died. There was no shore, just a 6-10 foot unclimbable cliff and a strong current pushing offshore. The only sure, safe option was to abort. If I didn't it would have been entirely on me. Diver error.

I'll go one further. If your equipment fails it's probably your fault as well. The chance of properly maintained equipment failing is miniscule. About the only things that might qualify as not equipment failure and not diver error that I can think of is if a regular air tank was filled with Nitrox and the diver exceeded the MOD or a tank had a lethal level of CO.

It could be argued that even these are diver error because some would say you should test every tank for O2 concentration and CO level. I don't think many do. Personally I trust the dive shop to be spot on in filling tanks (short fills excepted).

I guess that leaves medical issues. A heart attack or collapsed lung or other deadly medical issue is really about the only thing I can think of that doesn't fall under equipment or diver failure. For those - you pays yo money and you takes yo chance. Personally, I'm pretty sure I've got to die from something. I'd rather it would be from something beyond my control.
 
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Kharon, you take an interesting view of the world. There appears to be an assumption that if you can control it, and you don't and it ends up in adverse situation, you made an error. The problem with that position is that error has a negative connotation, same as violation, which means that when people make those errors they are afraid to talk about them because of the social pressures which will be laid upon them. From previous discussions, I think you are quite unique in terms of your risk tolerance, but many people are influenced by others' behaviours and therefore they follow the situation because they don't have the experience to know any better.

As I said in the above article, it isn't about making errors that is the problem, because humans make errors all the time. We just do not have the mental capacity to monitor everything that is going on around us, process it and then make a decision accordingly, and importantly in a timely manner. We take mental shortcuts based on previous experiences and most of the time they work out fine.

The important piece is trapping them before they become catastrophic. In the example you gave, your decision making was biased by previous experiences, but if you hadn't had those, I am not sure your decision making would be the same. In hindsight you could be accused of making an error, but at the time you only have the information you have.

A better way to think of your example would be to look at what failed.

1. Dive plan changed but doesn't look like it was communicated effectively. Either not communicated, or understanding not checked, before the 1st dive happened.
2. DM left you behind, poor teamwork and communication. Why were you not near the group when the DM left? Either poor plan to which didn't ensure that everyone was at the meeting place before the DM left or poor executed.
3. Good decision to return to the boat and stay there. But why did the DM then not surface if one of the divers wasn't present. Did he know where you were? At what point did they decide "You were ok" or "I hope they are okay as I have no idea where you are"? So whilst you deviated from the plan, you saved the situation. Often humans are heroes when they break the 'rules'. Hindsight is a great way to decide if an error has taken place.

In terms of the other points.

1. I believe every gas cylinder should be analysed for O2 content. Not just hyperoxia but also hypoxia.Then once analysed marked up accordingly. Why do you trust the dive shop? Are they ones diving the cylinder if they've made a mistake? You can't taste the gas, so how do you know they haven't been human and made a mistake?
2. There is an assumption that people will do their work/job properly. So even if you send you gear to the shop to get done, how do you know that they have done a good job?
3. Unknown medical issues are indeed an unknown until the post-mortem, but look at the general fitness of divers. Whilst it isn't an error, they are certainly loading the risks against themselves.

It is essential to understand the motivation, experience and drivers of those involved in adverse situations if we are to improve safety. Just classifying it 'Human Error' helps no-one.
 
There appears to be an assumption that if you can control it, and you don't and it ends up in adverse situation, you made an error. The problem with that position is that error has a negative connotation, same as violation, which means that when people make those errors they are afraid to talk about them because of the social pressures which will be laid upon them

I believe Kahron is on point. It sounds to me that you are advocating avoiding personal responsibly so a diver can talk to other divers about their mistakes. First take personal responsibility, next do whatever it takes to resolve the issue so it never occurs again, and social pressures are grade school crap, so put on your big guy (girl) pants and listen to the folks that help you and ignore the d**ks.


Bob
-------------
A diver, not a fragile flower.
 
I am not advocating avoiding personal responsibility at all. I am highlighting the fact that in many cases we do not actively make a decision. When you last went to the fridge and picked up a strawberry yogurt instead of a raspberry one, did you make that active decision? When you forgot to look in the mirror approaching a junction, did you chose to not look in the mirror? When you forgot to analyse the gas because you were distracted by a student asking an important question about their equipment, did you actively chose not to reanalyse the gas?

We make slips, lapses and mistakes all the time. We make errors all the time.

"Safety is not the absence of accidents, but rather the presence of barriers and safeguards and the ability to fail safely." - we cannot prevent human error. Period. What we can do is prepare people for the stuff that goes on and that means talking about it, and why it made sense to you at the time to do what you did. When someone speaks up and the social media world berates them for being 'stupid', then the next person is unlikely to talk about their mistakes for fear of social retribution. Even if those mistakes were about 'breaking the rules'.

In terms of peer pressure being school grade crap, is that why an F-18 crashed in the US recently, one of the factors cited was the inability to say no to a display when fatigued.

Navy Investigation Concludes Fatal Blue Angels Crash Caused By Pilot Error - USNI News

If you want to see how powerful social conformity is, watch this


Yes, we need to put on our 'big boy pants' but that is much easier to do when behind a keyboard than it is in the real world when you are not sure whether you are right and you don't know the other person.

Regards
 
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Unless something happened that precluded any possible desirable outcome then it is human "error".

A good example of a truly freak "accident" that could in no way be attributed to the diver was the cave-in that caused Parker Turner's death. There was nothing they could have done to have predicted the cave-in and nothing they could have done in response to have changed the outcome.

However, these kinds of events are very rare. In my opinion almost everything boils down to "human error" because somewhere along the line you either :

a) failed to avoid putting yourself in a situation that you were not prepared to handle adequately (avoid)
or
b) you failed to correctly handle a situation you *thought* you were prepared for (cure)

A good example of (a) is the death of Guy Garman in that crazy record attempt he made even after being warned that what he was going to try was insane and he wasn't properly prepared for it.

A good example of (b) are the ... what was it? .... 40% or so of accidents among recreational divers because they fail to follow good diving practices like checking their air or doing a buddy check and then subsequently end up dealing with a major event that was triggered by that.

In the case of (b), of course, there is a lot of ground that can be won but we have to admit that fixing "bad habits" is a game of diminishing returns because some people simply don't give a rat's patoot about good habits regardless of how much they are nagged about it.

On the other hand, I think that a lot of people do (a) because they are unaware of their incompetence. This is what we call "getting in over ones proverbial head". I think a lot of recreational accidents could be avoided as well if more diver's were more aware of their actual level of competency. The ground we can win here is enormous because getting out of this phase of being "incompetent and unaware" is part of a normal learning process and can be taught.

R..
 
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