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

Any system has failures because we cannot afford to engineer them out.

There are two themes you keep on throwing in regularly in your threads.

One I quote above.

The other is that Human Error is what drives rebreather fatalities.

On the first point, TRUE, but equally where you cannot afford to meet the requirements of an established current standard, and the product has a "SIL Level of less than one" - then you cannot go and produce marketing literature (print and internet) which leads the diver to believe the machine is safer than it is.

If it is "less than SIL one" - you cannot go and say it is safer or as safe as OC (not singling out Poseidon here, marketing bollocks is widespread).

That is the perfect example how the average recreational diver is misled as to the safety of the product he buys and/or uses.

The average OC diver has a mental picture of what OC diving is and what OC risk is, and the marketing bollocks precisely designed to link into that mental picture causes the diver to project himself as using a machine - the rebreather - at no further risk than OC diving and similarly to OC diving.

With that Projection in his mind, his behavior is that of someone undertaking one of the several OC dives he has done before - which is exactly what happened in this incident (at least that is my interpretation).

So, for someone like you who is so Human Factor driven, how difficult is it to see, after this incident, that Human Behavior, and as a consequence Human Success, and Human Failure, and Human Error - is dependent on Perception and Cognition and Projection?

Garbage IN = Garbage Out.

If you feed a human person misleading or incomplete information, the result is bad decisions/behavior, and when this involves a rebreather which can easily kill you without warning, then you have a fatality.
 
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If you feed a human person misleading or incomplete information, the result is bad decisions, and when this involves a rebreather which can easily kill you without warning, then you have a fatality.

This is only true if the teaching is done by the marketing brochure. However, I believe that the teaching is done by the manual. If you read the manual you'll see that Poseidon is perfectly clear about the dangers of CCR diving and that there are ample warnings that it's perfectly capable of killing you.

Marketing is marketing and teaching is teaching, do try to not mix them.

I for one cannot believe that this diver was taught the Disco with "misleading or incomplete information". If you don't know this for a fact then please stop spreading such lies around the forum.

/nils
 
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Gian,

I am getting fed up with this. The same repetition of the same problem and then copying words from previous posts which you have dismissed as being irrelevant, inferring that they are new ideas.

Right at the start of this I mentioned risk and risk perception and how that shapes behaviour and even if you engineer out a solution, you can still have someone find a 'novel' solution to breach those defences. Most of the breaches are by those who know the 'rules' and then intentionally break them (I did). So informing them of the risks does very little, you have to change behaviours. Changing behaviour in a structured organisation is difficult even when you have both carrots and sticks; we still have military aircrew kicking the arse out of low flying! When you are trying to change behaviours in a recreational, discretionary activity, it takes positive peer pressure to effect change. I was aware of the risks I was taking and mitigated them by OC bailout and a buddy, I could have mitigated them further by undertaking training but my own personal risk/benefit analysis said bollocks to that, I'll take the opportunity (time) and do it now. Humans are impatient, lazy, inattentive, naive, arrogant...all the things that do not help us when risks are out there which we could stop from turning into issues by saying no. Behaviour is a function of the person and their environment...

The part about being able to afford to engineer out solutions - Alex has already said that his work to get to where he is on the APOC and the other rebreathers (which are yet to get to market) have cost several million pounds, and that doesn't even cover the NRE to set up and run the business. (I don't care where the money came from, it costs money). If you don't have access to beneficiaries who are going to recoup costs through profit, they must come from customers. The sport diving industry is VERY small and will get smaller as litigation means companies pull out. As the number of units gets less, the unit price goes up. There are divers out there who dive air to 50-60m because they don't want to pay for Trimix. Dropping ***163;5-15k on a CCR is not going to happen for a large percentage of the population.

Regarding the standard, as far as I know it is not MANDATORY to comply with CE but it is a good idea as it allows you to sell the unit (and teach on it/using it) in the UK.

As an aside, what is the SIL of an OC dive?
 
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Gian, look at this paper

Human error and violations in 1,000 diving incidents: a review of data from the Diving Incident Monitoring Study (DIMS)
South Pacific Underwater Medicine Society 35:1, 11-17 (2005) which is available on Rubicon (on iPad so can't easily get link) and you will see some of the violations on OC. Why would they be any different on CCR?

25% of violations were conducted by DMs and Instructors, those who should know better...

Regards
 
Gian,

I am getting fed up with this. The same repetition of the same problem and then copying words from previous posts which you have dismissed as being irrelevant, inferring that they are new ideas.

Right at the start of this I mentioned risk and risk perception and how that shapes behaviour and even if you engineer out a solution, you can still have someone find a 'novel' solution to breach those defences. Most of the breaches are by those who know the 'rules' and then intentionally break them (I did). So informing them of the risks does very little, you have to change behaviours. Changing behaviour in a structured organisation is difficult even when you have both carrots and sticks; we still have military aircrew kicking the arse out of low flying! When you are trying to change behaviours in a recreational, discretionary activity, it takes positive peer pressure to effect change. I was aware of the risks I was taking and mitigated them by OC bailout and a buddy, I could have mitigated them further by undertaking training but my own personal risk/benefit analysis said bollocks to that, I'll take the opportunity (time) and do it now. Humans are impatient, lazy, inattentive, naive, arrogant...all the things that do not help us when risks are out there which we could stop from turning into issues by saying no. Behaviour is a function of the person and their environment...

The part about being able to afford to engineer out solutions - Alex has already said that his work to get to where he is on the APOC and the other rebreathers (which are yet to get to market) have cost several million pounds, and that doesn't even cover the NRE to set up and run the business. (I don't care where the money came from, it costs money). If you don't have access to beneficiaries who are going to recoup costs through profit, they must come from customers. The sport diving industry is VERY small and will get smaller as litigation means companies pull out. As the number of units gets less, the unit price goes up. There are divers out there who dive air to 50-60m because they don't want to pay for Trimix. Dropping ***163;5-15k on a CCR is not going to happen for a large percentage of the population.

As an aside, what is the SIL of an OC dive?

If I may, I think you have a mental projection of what your Ph.D. thesis will show (this shows in many snippets of your posts), and where I may be an irritant is that I am challenging that mental projection when I say that Human Error is a consequence of the process of Perception, Cognition, and Projection (and Garbage IN = Garbage Out).

I'll give you reference to a good book:

Situation Awareness Analysis and Measurement Mica R. Endsley (Editor), Daniel J. Garland (Editor)

On the aside, OC diving is pretty safe, exactly the opposite of rebreather diving.
 
I'll take your guidance on what Human Error is thanks...

Did you bother reading the link I posted about the PhD scope? If you have you will see what I am aiming towards...

Regards
 
This is only true if the teaching is done by the marketing brochure. However, I believe that the teaching is done by the manual. If you read the manual you'll see that Poseidon is perfectly clear about the dangers of CCR diving and that there are ample warnings that it's perfectly capable of killing you.

Marketing is marketing and teaching is teaching, do try to not mix them.

I for one cannot believe that this diver was taught the Disco with "misleading or incomplete information". If you don't know this for a fact then please stop spreading such lies around the forum.

/nils

The teacher is an information taker same as the student.

I never said anything about the training of the diver who passed away on the Disco.

I assume he took the course and passed it (as much I kind of gather, but I was not there).
 
The teacher is an information taker same as the student.

I never said anything about the training of the diver who passed away on the Disco.

I assume he took the course and passed it (as much I kind of gather, but I was not there).

Your answer makes no sense at all. Unless you're implying that the teacher himself had no further training than reading the marketing brochure?!

And actually you did say a lot about the training, or are you unaware of the content of your post - the one I qouted? In fact you have been going on a lot about the (lack of) training.

Now, if he took the course - which includes reading the manual - then he had all the warnings a person can get, wish for or ever need. Do you understand this, yes or no?

/nils
 
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Your answer makes no sense at all. Unless you're implying that the teacher himself had no further traing than reading the marketing brochure?!

And actually you did say a lot about the training, or are you unaware of the content of your post - the one I qouted? In fact you have been going on a lot about the (lack of) training.

Now, if he took the course - which includes reading the manual - then he had all the warnings a person can get, wish for or ever need. Do you understand this, yes or no?

/nils

Where in any one rebreather manual does it say the product does not meet Clause 5.13.1 (i.e. Functional Safety) of the current rebreather standard EN14143:2003?

How would the instructor be expected to know if he is not told?

How could the instructor inform the student if he is not told?

By all means, I am not saying the MKVI is a bad rebreather.

I love the design and concept and would buy one myself (if I only knew what the WOB was).

It is the smartest and best thought rebreather ever made.

It is just that rebreathers because of the current state of the technology are very dangerous and not safer or as safe as OC diving.

For a 10 -12 meter dive, the last tool you want to use is a rebreather, given the risk inherent in the rebreather technology.
 
Where in any one rebreather manual does it say the product does not meet Clause 5.13.1 (i.e. Functional Safety) of the current rebreather standard EN14143:2003?

How would the instructor be expected to know if he is not told?

How could the instructor inform the student if he is not told?

By all means, I am not saying the MKVI is a bad rebreather.

I love the design and concept and would buy one myself (if I only knew what the WOB was).

It is the smartest and best thought rebreather ever made.

It is just that rebreathers because of the current state of the technology are very dangerous and not safer or as safe as OC diving.

For a 10 -12 meter dive, the last tool you want to use is a rebreather, given the risk inherent in the rebreather technology.

Since my question obviously was to complicated for you:

If he took the course - which includes reading the manual - then he had all the warnings a person can get, wish for or ever need. Do you understand this, YES or NO?

/nils
 
Gian, answer yes/no. Have you read the manual?

Did you read the part early on which talks about compliance to the CE? Can't give page as on iphone.

Regards
 
I look at it this way

you have the guys wanting to make and sell the best breather thay can
then you have the guys that want to build a breather that will kill but when it happens they wont get the blame

CCR market is prob no its arse , ( new punters are always needed) . the new punters not needed by me
but BY all them that want to make a living out of breather ,

X trymix diver go,s and gets a 2nd hand breather pays for mod1
thats it hes off diving to 80m happy as a pig in poo , 2k all in

noddy diver go,s and gets a new ccr 5k+
takes a course 500 , gos diving
6 weeks later hes back wants to go deeper , new course needed
1 year later he,s back a gain want,s to go deeper and do a shit load of deco
no problem we have just the course , your looking at 10k per new punter


i do not worry about noddy dives using a breather , if they want to .

but each time a ccr diver gets killed , its a black mark on my pass time
all my cost will prob go up , insurance and the like ,
guys that at one time made stuff i wanted to buy for my breather stop selling me stuff just in case i kill my self ,

internet is full of o my god a ccr diver is dead, so what , thousand die each day ,

all this talk about how safe things are will do feek all to help ccr divers ,
this guy that passed away on the unit, he was at work so let the HSE or who ever sort it ,

ccr diving is my hobby not my work , i dont want a load of forum guru,s telling me its going to kill me if i dont watch my arse , as i know that all ready ,

the noddy story about the try dive and diver knowing feek all about the unit , im all for it , kill the feeking lot in one go and lets get on with are diving .

now i know a guy that had a unit in his home for 2 year never dived it , but read and read all he could , went to his club pool night and did some drill,s on said unit , then did his mod1 a few weeks later , after 20min on his unit he was on the ball , the rest of the week was just 30m diving with a few drills tossed in, fab weeks diving in the red sea . back home he had a days cold water diving trying out his dry suit with his unit , job done , week after hes in 75m no problems ,

only problem with guys like him is , you cant get moooooo money out of them,

punter,s will in the end be the death of ccr diving , no matter how safe you make them .. keep the punters away , for me and my pass time , i like the risk , and the diving , if you dont like the odd,s dont dive a breather ,

One day
The hse and all the other government or state agency,s will come and dump on are weekend ,

im v happy diving my none to safe breather , :haddock:

and i dont want to see it regulating , or used on the net to make a few quid FOR some ,

just sort the o2 cell s and the rest i can do , thank,s , :guitarist


ps even death makes money , for them that want to teach noddy,s to die on a breather ,

make,s the rest/other new noddy,s shit them self,s , and go get lots of training in the hope they will live longer , lol
 
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Since my question obviously was to complicated for you:

If he took the course - which includes reading the manual - then he had all the warnings a person can get, wish for or ever need. Do you understand this, YES or NO?

/nils

Of course the answer is NO.

I see nowhere in any rebreather or training manual the disclosure that the machine does not meet Clause 5.13.1 (Functional Safety) of the current rebreather standard EN14143:2003.

Functional Safety must take into account of Human Factors and regretfully in this incident a simple and inexpensive design could have prevented the fatality.

Furthermore, Functional Safety assigns a probability of occurrence of a dangerous failure and sets a maximum limit as the maximum risk which the rebeather must have to achieve Functional Safety.

Merely listing the risk (i.e. hypoxia, hyperoxia, hypercapnia) is not enough as it is entirely different to disclose what the probability of those event occurring is.

Couple that with the marketing bollocks of it is safer or as safe as OC diving...

Look at where selling CMBS (Collateralised Mortgage Backed Securities) under the marketing slogan "As safe as houses" got the world to!
 
Of course the answer is NO.

I see nowhere in any rebreather or training manual the disclosure that the machine does not meet Clause 5.13.1 (Functional Safety) of the current rebreather standard EN14143:2003.

Functional Safety must take into account of Human Factors and regretfully in this incident a simple and inexpensive design could have prevented the fatality.

Furthermore, Functional Safety assigns a probability of occurrence of a dangerous failure and sets a maximum limit as the maximum risk which the rebeather must have to achieve Functional Safety.

Merely listing the risk (i.e. hypoxia, hyperoxia, hypercapnia) is not enough as it is entirely different to disclose what the probability of those event occurring is.

Couple that with the marketing bollocks of it is safer or as safe as OC diving...

Look at where selling CMBS (Collateralised Mortgage Backed Securities) under the marketing slogan "As safe as houses" got the world to!

Oh... alright. Well if you're uncapable of grasping the difference between marketing and teaching your not worth my time.

/nils
 
Regarding the standard, as far as I know it is not MANDATORY to comply with CE but it is a good idea as it allows you to sell the unit (and teach on it/using it) in the UK.

no, it's different

In Europe it's mandatory to comply with the CE regulations.

It is however not mandatory to comply with the EN14143:2003: the PPE directive (wich is the law to obay) that includes the CE regulations, allows two paths to follow:

1 using the EN14143:2003
2 using the route of the 'technical file'

both routes can end up (if succesfull) to a correct CE type approval
 
Oh... alright. Well if you're uncapable of grasping the difference between marketing and teaching your not worth my time.

/nils

I answered your question and now you run because you are unable to put forward a counterargument.

You are shifting responsibility for the product and the manual on the instructor.

The instructor has no way of knowing what the SIL Level and probability of failure of the machine is, and is in no position to communicate it to the student.

My MOd 1. instructor at the end of the course he told me to "Dive Safe!"

What, on a rebreather???
 
no, it's different

In Europe it's mandatory to comply with the CE regulations.

It is however not mandatory to comply with the EN14143:2003: the PPE directive (wich is the law to obay) that includes the CE regulations, allows two paths to follow:

1 using the EN14143:2003
2 using the route of the 'technical file'

both routes can end up (if succesfull) to a correct CE type approval

No.

A "technical file" is required for both path 1 and path 2 above.

As explained in the following video, a route 2 "success" (i.e. a "CE" mark) can be achieved even with a supermarket bag (i.e. no Functional Safety).

The video is available for download here:

DAN Divers Alert Network

under the section Day 2 Morning: "Diving re-breathing apparatus: Testing and standards, UK/EU Perspective What is the European Union (EU) CE mark and how do you get it? The principles and physiological basis for the testing required by the harmonised standard (EN 14143) are presented and discussed including: manned and unmanned UK test procedures for rebreathers; performance parameters and standards; work of breathing, peak to end pressure, O2 and CO2 control; hydrostatic imbalance, breathing bag location, and diver position; and gas density and end-tidal CO2."

tfreq.jpg
 
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Tell you what Gian. I'm more inclined to trust Paul who does this for a living ... and has a vested interest in not getting his ass sued...

Regards
 
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