Functional Safety, Human Factors and General Safety Discussion (Moved from Mk VI)

[Chris Brown]

You might be reading with a bias chris. Its the 'Safer and easier to use than OC' bit that people are grizzling about

I hear ya. Not sure I agree with either statement, but I dont read it as gospel either. Theres no black and white in diving, so I dont see why everything has to be so literal. In some instances the MKVI would be safer than OC in my opinion, such as compared to a single 80 on a 100' drift dive in Cozumel, but not necessarily on a 20' deep reef.

I was really just countering the comment that it was surely an April fool to be taching inexperienced divers on the MKVI. Thats exactly what its supposed to be for!!

Also, its fair to say that experienced OC divers and instructors tend to do really well on CCR induction too. Its those people in the middle, a bit like the 100 hour pilots

At the end of the day, If Poseidon mentioned chuff all about the three H's and the dangers associated with CCR diving, then Id agree. The manual and training spell it all out, so if you buy one, read the manual, take the training and then jump in thinking theres zero risk because the marketing blurb said it was safer than OC, then theres not really any hope for you.

Square shutes are safer than round ones by the way.

 

[MeRodent]

If no machinery were involved, then you could talk about Human Factor in isolation.

BUT, in our application, machinery is involved, and its life-support is entirely dependent on electronics and human interaction.

I am taking a break seriously cause tomorrow will be the whole day shooting my Made in the U.S.A. superior technology and it is a long ride.

Gian, I suspect that given your emphasis on engineering out the human factors as a cause of accidents that you strongly complain to the "superior technology" USA manufacturers of weapons that they engineer out the possibility of shooting another human. Ie expect target identification systems that can lock out the trigger if the weapon is pointed at a human rather than rely on the "human factors" of teaching shooters to look for other humans down range. No doubt you have included modifications to your weapons as this sort of thing is not currently available despite some centuries of guns and weapons being developed?

 

[gianaameri]

Gian, I suspect that given your emphasis on engineering out the human factors as a cause of accidents that you strongly complain to the "superior technology" USA manufacturers of weapons that they engineer out the possibility of shooting another human. Ie expect target identification systems that can lock out the trigger if the weapon is pointed at a human rather than rely on the "human factors" of teaching shooters to look for other humans down range. No doubt you have included modifications to your weapons as this sort of thing is not currently available despite some centuries of guns and weapons being developed?

The Range is designed in a particular way taking into account the machine (i.e ballistics) and Human Factors (and the village way past the horizon, but at easy reach of a .338).

Nonetheless, you have to "Know what you are shooting" and Situational Awareness is the link between desired and unwanted results.

Off for a long drive!

 

[Mark Rowe]

Hello Mark,

Thanks for this observation. I agree that exercise would sharpen the sensitivity, but most divers don't exercise during their pre-breathe and we will probably just run the study at rest.... at least initially. I want it to be practically useful, and to answer the question "can a 5 minute pre-breathe reliably detect the absence or complete bypass of a CO2 scrubber"? The rebreather condition will need to be blinded to the participant. In other words, some trials will involve a rebreather without the scrubber and some will be correctly assembled, but the subject will not know which is which. We will have to develop a "completely expended canister model" so that the WOB is not obviously lower when the scrubber is omitted. We will need to repeat the experiment enough times so it is not just anecdote, and so we can confidently say that a diver can detect an absent scrubber during a 5 minute pre-breathe X% of the time. We will probably move on to testing a couple of partial failure modes after that (such as leaving the O ring out of the inspo assembly). One possible outcome might be that it is easy to detect an absent scrubber with a 5 minute pre-breathe (although some have disputed this), but that partial failures are less reliably detected (or not detected at all).
Simon M

Hi Simon, Gareth et al.
Some of the heated discussion is not in my expertise but Gian I'm not sure that safety can always be built it because CCR diving is dangerous. The human factor (the fool) must take account for his actions if he does an activity that is known to be unsafe but does it anyway. Eg no pre breathe on a CCR or smoking while filling your car!!! Both have been done and both potentially don't end well but a manufacturer can't factor out the idiot. Driving is dangerous - we all know and accept it is, it kills thousands of people every year but we all accept the fact, we got a good instructor, purchased the safest, most affordable car and normally drive it safely. Same can be said for diving and CCR diving.

Thought you might like to know that SSI now do open water diver on the MK6

As an aside and I'm sure I'm not the first (I hope as how do you know what it feels like for real) I did a pre breathe on my MK6 yesterday - static, 5 minutes sat down. I videoed it on my gopro - yet to review the video. After three minutes my breathing rate was up and continued to increase the last two minutes. Only had a slight head ache at the 5 min point, but it increased after finishing.
It did show me what it felt like and I know that five mins is the minimum static. As I said already if you want to really test then perhaps walk and do the pre breathe - the exercise will show any issue in the 5 minutes - or do longer static.
@simon I move to the Dominican Republic at the end of May (teaching rec and Tec diving) but if it fitted in with everything I've got to do and timings I would volunteer for your experiment - location depending, the my MK6 is available then too as a unit.
Safe diving
Mark

 

[Mike Ferguson]

I was really just countering the comment that it was surely an April fool to be taching inexperienced divers on the MKVI. Thats exactly what its supposed to be for!!

chris

what worries me is the safer and easier and no deco claim being misleading to the target market which quite clearly are divers with little (actually for 15 dives that should be no) real experience and who aren't in a position to see through the marketing BS.

mike

 

[GLOC]

chris

what worries me is the safer and easier and no deco claim being misleading to the target market which quite clearly are divers with little (actually for 15 dives that should be no) real experience and who aren't in a position to see through the marketing BS.

mike

My local club is having a try-dive session in the pool in 3 weeks time with Mk VI, I might go along and see what the 'marketing' is. Knowing one of the characters involved, I won't trust him to do any teaching of anyone I know. However, it appears to be run by Poseidon.

The problem with all of this is the lack of consistency of the instructors which should identify the weaknesses in the 'system' to the potential client and no means to trap those instructors without having a commercial impact on the 'product'. However, I know of one Mk VI instructor who is trying to short cut his hours development by getting someone else to use his battery to log hours and when I mentioned this to the agency they said that they had processes in place to catch this...

Regards

 

[cathal]

"Driving is dangerous - we all know and accept it is, it kills thousands of people every year but we all accept the fact, we got a good instructor, purchased the safest, most affordable car and normally drive it safely. Same can be said for diving and CCR diving."

Sums this discussion up well. No matter how much you eliminate any risk involved with operating a rebreather even as to as low as is reasonably practicable (ALARP) there still will be fatalities as you cannot engineer out the idiot factor.

All the best

Cathal

 

[Chris Brown]

chris

what worries me is the safer and easier and no deco claim being misleading to the target market which quite clearly are divers with little (actually for 15 dives that should be no) real experience and who aren't in a position to see through the marketing BS.

mike

Yes, I can can understand the concern. I havent yet had a discussion with a new diver or ccr diver who wasnt aware of the dangers.

Conversely, I remember my own OW training where I was a bit miffed to find out during module 1 that you could suffer a lung over expansion injury. That was news to me and only disclosed on the video after I'd paid, bought my mask, fins, snorkels etc.

People who already dive know the dangers better than those new to the sport IMO

 

[GLOC]

On a side note, how do you convince your students to do this...? :uhh:

Yes, a good question that I will leave to the behavioural change experts like Gareth

.

Because they trust him! And they trust the process they are involved in. Society works on trust; police, doctors, armed forces...OW instructors when you are doing your OW, CCR instructors when doing Mod 1. There is an interesting experiment Milgram experiment which took this to the extreme (I am not sure Simon will go this far ; that is what ethics committees are for!) but the concept is the same. We were given a lecture at staff college about prisoner handling and the lecturer said that there is no such thing as bad people, just bad situations, and then went on to say that of the 300 or so senior officers in the audience, 70% would likely follow something like Abu Ghraib until someone had the moral courage to say stop.

At a more operational level, the ability for someone who is less experienced to question those above them in authoritative or experience roles is crucial to developing and maintaining a Just Culture. This is fairly well developed in commercial and military aviation (removing cross-cockpit gradient), and is starting to come into operating theatres (consultant surgeon is 'god') but in diving, the concept of Crew Resource Management (CRM) is somewhat lacking at the wider community level. If your instructor is an auto-crat, you may not be able to raise concerns over his configuration or diving when he is making a mistake. If you are an inexperienced diver with some 'gods' that you look up to and respect, depending on their attitudes and openness, you may not be able to prevent something from happening.

Regards

 

[Paul Haynes]

Poseidon***8217;s MKVI has significant advantages over traditional open circuit equipment:
3 hours typical dive time
Safer and easier to use
Lighter and smaller
No decompression stops


Yes Poseidon's marketing is unsettling although clearly they are the last people who want accidents with their units. Here is an extract from an article I wrote for a dive magazine (waiting to be published) that relates to what might be going on in the industry:


Having now reviewed the ghosts of rebreather past, what of the future? Is the rCCR a cynical commercial effort to generate new income from what many believe is a contracting sport diving market or is it a genuine effort to enhance recreational diving experience and promote sport diving? Taking an objective view, both the manufacturers and training agencies are commercial entities, which like any business survive only by making a profit. A conclusion could therefore be made that to a certain degree, it must be a combination of both these factors, which together provide a business growth feedback loop. What must also be considered is that training agencies and manufacturers clearly wish to see a fall in rebreather incidents and as a result, significant effort has and is being made by many of the top thinkers in the industry regarding how to address the numerous equipment and training issues associated with mainstream rCCR use. However not everyone is convinced and to quote the CEO of a well respected sport / military rebreather manufacturer: we have a broken safety culture as a result of compromise and complacency. Now we are feeding that machine by telling people what they want to hear. Rebreathers are NOT for everyone. The final sentence rebreathers are NOT for everyone is a widely held belief by many and as the dive industry marketing machine gears up, concerns over the rCCR concept is being further agitated. A widely publicised rCCR advertisement stated: Open the tank valves, wet the switch on the back of the display, wait for the systems check and off you go. Forget everything you ever heard about PO2, scrubber life and oxygen cells. Oxygen partial pressure and scrubber life, the two most safety critical elements of rebreather diving and the customer this advert is aimed at, the mainstream diver, is being advised to forget about them! Such advertisements are alarming and feed the fire of controversy. The diving marketing industry should therefore consider very carefully the messages they are trying to communicate in order not to undermine the work being done by those striving to address the many rCCR training and safety challenges.

 

[gianaameri]

Poseidon***8217;s MKVI has significant advantages over traditional open circuit equipment:
3 hours typical dive time
Safer and easier to use
Lighter and smaller
No decompression stops


Yes Poseidon's marketing is unsettling although clearly they are the last people who want accidents with their units. Here is an extract from an article I wrote for a dive magazine (waiting to be published) that relates to what might be going on in the industry:


Having now reviewed the ***8216;ghosts of rebreather past***8217;, what of the future? Is the rCCR a cynical commercial effort to generate new income from what many believe is a contracting sport diving market or is it a genuine effort to enhance recreational diving experience and promote sport diving? Taking an objective view, both the manufacturers and training agencies are commercial entities, which like any business survive only by making a profit. A conclusion could therefore be made that to a certain degree, it must be a combination of both these factors, which together provide a business growth feedback loop. What must also be considered is that training agencies and manufacturers clearly wish to see a fall in rebreather incidents and as a result, significant effort has and is being made by many of the top thinkers in the industry regarding how to address the numerous equipment and training issues associated with ***8216;mainstream***8217; rCCR use. However not everyone is convinced and to quote the CEO of a well respected sport / military rebreather manufacturer: ***8220;we have a ***8216;broken***8217; safety culture as a result of compromise and complacency. Now we are feeding that machine by telling people what they want to hear. Rebreathers are NOT for everyone.***8221; The final sentence ***8220;rebreathers are NOT for everyone***8221; is a widely held belief by many and as the dive industry ***8216;marketing machine***8217; gears up, concerns over the rCCR concept is being further agitated. A widely publicised rCCR advertisement of stated: ***8220;Open the tank valves, wet the switch on the back of the display, wait for the systems check and off you go. Forget everything you ever heard about PO2, scrubber life and oxygen cells***8221;. Oxygen partial pressure and scrubber life, the two most safety critical elements of rebreather diving and the customer this advert is aimed at, the ***8216;mainstream***8217; diver, is being advised to forget about them! Such advertisements are alarming and feed the fire of controversy. The diving marketing industry should therefore consider very carefully the messages they are trying to communicate in order not to undermine the work being done by those striving to address the many rCCR training and safety challenges.

Rebreather advertisements to mainstream divers has been around a long time (i.e. many many years).

It is not a recent phenomena and Mod. 1 is precisely designed for mainstream divers buying a rebreather for the first time.

I was a normal OW diver when I bought my first rebreather and the marketing then was not substantially different from what is happening today.

The manuals had the same list of the generic risks (i.e. hypoxia, hyperoxia, hypercapnia) which the MKVI manual has, and there was not, as there is not now, any proper disclosure covering the actual Probability of those event occurring (i.e. the rebreather being "less than SIL one" lacking Functional Safety and having a high Probability of Failure. that is well above that required by the current rebreather standard).

It is not a problem unique to Poseidon or a new one. It is and has always been what the industry has chosen to do in terms of marketing its product.

By all means, I am not saying it is illegal (if it were, it would not be happening), just an issue of ethics and morality when full disclosure as to lack of Functional Safety (i.e. Clause 5.13.1 of the current rebreather standard EN14143:2003) is not generally provided to users and potential users before they buy the product.

I suspect this may be happening more frequently that we can imagine also for other products (i.e. commercial interests driving marketing spin), but for other products we are not generally seeing the fatalities we are seeing in rebreathers sold and used for sport/recreational activities.

 

[GLOC]

I suspect this may be happening more frequently that we can imagine also for other products (i.e. commercial interests drive marketing spin), but for other products we are not generally seeing the fatalities we are seeing in rebreathers sold and used for sport/recreational activities.

Evidence please.

Regards

 

[gianaameri]

Evidence please.

Regards

More than 280 dead, ain't it enough???

https://www.google.co.uk/url?sa=t&r...=khZeJbNmx6yed9fuF4Vt2g&bvm=bv.45960087,d.ZG4

 

[gianaameri]

GLOC,

why don't we compare another sport recreational activity to rebreather diving.

Let us pick one which by virtue of your job you may have easy access to statistic: civilian recreational sport shooting on MoD (UK Ministry of Defense) Ranges.

To put it in context for those who have never been in one, on a week-end they are very very busy.

Shooters are as young as 10 (my youngest son shoots shotgun there).

Teenagers shoot semi-auto and larger calibres up to .308/7.62 (bolt action sniper rifles).

Grown-ups shoot .338 Lapua Magnum and 50 cal. (good fun!).

80% are the elderly. Not fit, and probably on prescription medication (although none which ought to impair their functions as far as I know).

Bear in mind that as we get older we also lose a little bit in dexterity and Situational Awareness (not to say that teens are not capable of incredible faux-pas of their own).

Firearms are notoriously dangerous (not as dangerous as rebreathers because shooting a firearm you won't go unconscious without warning and drown).

A bullet can be lethal for several miles.

I'd say there are far more civilian shooters than rebreather divers in the U.K. (with a bit of work we could get some numbers and I think it would show the assertion to be reasonably correct).

More than 280 fatalities to date on rebreathers, and, you tell me for comparison, how many sport recreational shooting civilian fatalities on U.K. Ministry of Defence firing ranges to date?

This you may know, but you may not tell due to the OSA, how many military fatalities from shooting in training on U.K. Ministry of Defence firing ranges to date?

 

[Mark Rowe]

Rebreather advertisements to mainstream divers has been around a long time (i.e. many many years).

It is not a recent phenomena and Mod. 1 is precisely designed for mainstream divers buying a rebreather for the first time.

I was a normal OW diver when I bought my first rebreather and the marketing then was not substantially different from what is happening today.

The manuals had the same list of the generic risks (i.e. hypoxia, hyperoxia, hypercapnia) which the MKVI manual has, and there was not, as there is not now, any proper disclosure covering the actual Probability of those event occurring (i.e. the rebreather being "less than SIL one" lacking Functional Safety and having a high Probability of Failure. that is well above that required by the current rebreather standard).

It is not a problem unique to Poseidon or a new one. It is and has always been what the industry has chosen to do in terms of marketing its product.

By all means, I am not saying it is illegal (if it were, it would not be happening), just an issue of ethics and morality when full disclosure as to lack of Functional Safety (i.e. Clause 5.13.1 of the current rebreather standard EN14143:2003) is not generally provided to users and potential users before they buy the product.

I suspect this may be happening more frequently that we can imagine also for other products (i.e. commercial interests driving marketing spin), but for other products we are not generally seeing the fatalities we are seeing in rebreathers sold and used for sport/recreational activities.

First time I'm actually agreeing with some of your text. However..... If you want another example look at car ads and hype - no where does it say this metal box will potentially kill you - In fact the opposite, some go to great lengths to show off safety features which probably all would save your life if you and all other road drivers - human factor idiots didn't disobey the rules of the road or drive said safety metal box outside its tested design envelope.

Safe driving

 

[gianaameri]

First time I'm actually agreeing with some of your text. However..... If you want another example look at car ads and hype - no where does it say this metal box will potentially kill you - In fact the opposite, some go to great lengths to show off safety features which probably all would save your life if you and all other road drivers - human factor idiots didn't disobey the rules of the road or drive said safety metal box outside its tested design envelope.

Safe driving

Yes, but do car manufacturers find a short-cut to get their cars certification and not tell the implications (i.e. "we found a short-cut and are circumventing the CE standard car safety requirements for cars...?")

Maybe they do... it'd be pretty scary though!

 

[Mark Rowe]

I don't think rebreather manufacturers short cut either, they are designed as is, are tested and certified as is. Why does the unit have to provide a holly grail 'keep you alive' at all costs - the human in the loop is and must be part of the design solution. What other system provides that holly grail when conducting an activity that would potentially kill you? Can't think of one?

 

[gianaameri]

I don't think rebreather manufacturers short cut either, they are designed as is, are tested and certified as is. Why does the unit have to provide a holly grail 'keep you alive' at all costs - the human in the loop is and must be part of the design solution. What other system provides that holly grail when conducting an activity that would potentially kill you? Can't think of one?

Paul, a manufacturer, has clearly explained to us he can use, and I believe he does, a "Technical File" to certify a rebreather and he is under no obligation to meet Clause 5.13.1 of the current rebreather standard EN14143:2003.

He writes the "Technical File" and then submits it to RINA who then certifies the rebreather.

Paul has two routes to chose from, and it is up to Paul which one he goes for.

This is what I understand.

 

[GLOC]

More than 280 dead, ain't it enough???

How many of these were directly attributable to lack of a declaration of Functional Safety??

In General Aviation (GA) in the US between 1990 and 2000 there were 3256 fatal and 11180 non-fatal accidents [1] which had aircrew error as a casual factor. This report does not show the attribution for equipment failure but I think I can get it from another report but not likely to be for the same time period; however, from memory it will be in the order of a few percentage points. The Fatal Accident Rate per 100 000 hrs is in the order of 1.5 [2] from an ANNUAL fatality rate of around 550-600. Aircraft flown in General Aviation will have Functional Safety Certifications inline with FAA requirements.

The following images from this report show where the 'Unsafe Acts' are broken down into. The labels on the graphs are relatively self-explanatory.

So, even in an environment which has a functional safety requirement, has a significant amount of bureaucracy and oversight (although not to the same level as commercial or military aviation), we still end up with violations causing in the order of 30% of fatalities. The survivability rate between non-fatal and fatal accidents is quite surprising when it comes to violations; you are more likely to kill yourself if you violate the rules than make an error.

I was typing this up when your shooting analogy came in. I don't think it is a fair comparison because you need to have a licence to shoot. If you commit a violation, you either are thrown out of the range and/or end up in jail. In diving, there are no dive police and it is up to YOU to make the decision about breaking the rules, or keeping current in your skills . This is not the case in shooting where you have a direct level of supervision.

I was thinking about violations the other day when I was driving up for a meeting and doing a little over the speed limit. I know I am breaking the rules, but am I more worried about injuring myself or someone else, or am I more worried about getting caught by the police?

A final analogy for you to think about - Freefall parachuting and the CYPRES Automatic Activation Device http://www.cypresusa.com/userguide/CYPRES_2_Users_Guide_English_01-2013.pdf

Every technical device can fail. So everything imaginable can happen with the CYPRES, including, but not limited to: displaying a status which is not true, failing to function, or functioning at a wrong moment or at a wrong occasion. If you or your friends or family are not willing to accept these uncertainties and risks, then please don’t use CYPRES. - page 9

The Disclaimer is on page 46 and there is no mention of Functional Safety in there either.

Automatic activation devices (AADs) sometimes display a wrong status, fail to operate or operate properly, and sometimes activate when they should not, even when properly installed and operated. Therefore the user risks serious injury or even death to themselves and others during each use...Please note that even though CYPRES has an extraordinary track record, your results may vary.

[1] Wiegmann, D., Shappell, S., Boquet, A., Detwiler, C., Holcomb, K. & Faaborg, T., 2005, Human error and general aviation accidents: A comprehensive, fine-grained analysis using HFACS. Federal Aviation Administration.

[2] AOPA Online: General Aviation Safety Record — Current and Historic - we don't have a consistent fatality rate for diving (i.e. per divers, per dives, per hours in water) but the annual dive fatality rate from BSAC and DAN AP is in the order of 0.5 to 1:200 000.

 

[gianaameri]

How many of these were directly attributable to lack of a declaration of Functional Safety??

We cannot even tell from an autopsy of what the diver has died of (other than drowning).

Hypoxia, hyperoxya, and hypercapnia leave no traces in brain tissue (or any other tissue).

We all die of hypoxia and a bit of hypercapnia (the forum Dr. may tell us more, I am no expert).

So, let us cut the crap excuses.

There will never be any "proof" the rebreather has actually caused the fatality.

This does not mean that intelligent people cannot still reach some meaningful conclusions as to how the current situation could be made better and what could be tackled, and what not, and if not what disclosures could be made, which are not made.