Fatality on Mk VI in Portugal - April 2013

[psmedo]

Ben, (...) Part of my studies will be to look at why people make the mistakes they do

Just back to recomend this very "light" pocket book on the above subject where one can understand why and how we makes what apper to others "stupid msitakes"...

Nice reading and it may help your project GLOC.


Author Joe Hallinan: Why We Make Mistakes

 

[MeRodent]

Something that stops you diving without a canister would take serious suicidal tendencies, but what about alarms or protocols to stop you getting into the water without a complete system check being done, or where the system 'fails' but you 'know better'? (Sometimes the system fails but it is serviceable and so the user loses confidence in the system)

http://www.ccrexplorers.com/showpost.php?p=146569&postcount=208 (Functional Safety thread, post 208) onwards shows examples of people 'breaking the rules' and still going diving, and the potential reasons for this. Madness, until you are in that situation...

Regards

Absolutely agree with you here GLOC and I think your study into why people do these things is where we will get more based on understanding human factors than simply engineering solutions. Unfortunately it seems that the need to follow checklists needs to be driven home somehow. I can give a couple examples both ways.

On my dive course I saw a diver jump in post dive on CCR without running through his checklist to help a boat recover their anchor - simple dive but forgot to turn O2 on. He realised it during the dive but it brought home to me that ANY CCR dive - no matter how simple must be treated as a full dive from start to finish.

On the other hand despite having an employer that as part of safe working practices educates us constantly that driving while speaking on a car kit is as dangerous as holding the phone while driving I do find I will slip back into answering the phone before pulling over or letting the phone go to message bank.

 

[GLOC]

On my dive course I saw a diver jump in post dive on CCR without running through his checklist to help a boat recover their anchor - simple dive but forgot to turn O2 on. He realised it during the dive but it brought home to me that ANY CCR dive - no matter how simple must be treated as a full dive from start to finish.

This was likely the cause behind a fatality 3 or 4 years ago here in the UK too; only in small number of metres too Contradictory information at the inquest which didn't help.

Regards

 

[Mark Powell]

Just back to recomend this very "light" pocket book on the above subject where one can understand why and how we makes what apper to others "stupid msitakes"...

Nice reading and it may help your project GLOC.


Author Joe Hallinan: Why We Make Mistakes

That's a great book and has influenced my own thoughts on the topic. Some of the points from this book made it into my presentation at the UK dive shows on "Why Divers Do Stupid Things".

 

[Ben Field]

There is however a difference between errors caused by missing something (or even stupidity) and deliberately bypassing safety features. It should be possible to engineer out the former.

I'm not sure it is... you can do alot but some of the bypassing is done because of rushing or hitting a dealine (slack water etc), its not delibrate (while it is stupid) it is accidential- how often do smart divers jump in without turning their gas on?

Someone deliberately trying to bypass safety features probably deserves to be a Darwin Award winner - however even there it would be useful to understand why someone would want to bypass safety features.

How many times have you propped a Fire door open with a fire extinguisher?

People do things for unrelated reasons sometimes, you can easily forsee how a "smart" foolproof CCR might make some fault finding difficult on the bench unless bodged (you'll remember wetting your deco computer contacts to get it to start?)

 

[psmedo]

That's a great book and has influenced my own thoughts on the topic. Some of the points from this book made it into my presentation at the UK dive shows on "Why Divers Do Stupid Things".

Off course not dimizing your TEXTBOOK on DECO, Mark, a real must for all divers.

RGDS

 

[Mr fish]

Something that stops you diving without a canister would take serious suicidal tendencies, but what about alarms or protocols to stop you getting into the water without a complete system check being done, or where the system 'fails' but you 'know better'? (Sometimes the system fails but it is serviceable and so the user loses confidence in the system)

http://www.ccrexplorers.com/showpost.php?p=146569&postcount=208 (Functional Safety thread, post 208) onwards shows examples of people 'breaking the rules' and still going diving, and the potential reasons for this. Madness, until you are in that situation...

Regards

As soon as the unit turns its self on and try,s to keep you alive when it hits the water , all the alarms or protocols wont help ..

what you need is, if you don t do the full pre dive tests , then no dive. fall over board and the unit just free flows in to the tits and keeps you top side .

:rocker:

 

[MeRodent]

As soon as the unit turns its self on and try,s to keep you alive when it hits the water , all the alarms or protocols wont help ..

what you need is, if you don t do the full pre dive tests , then no dive. fall over board and the unit just free flows in to the tits and keeps you top side .

:rocker:

There you go a simple engineerable solution that not only stops the diver from risky behaviour but additionally punishes them (dive not possible) for their stupidity. In other words the diver doesn't go about thinking how do I bypass this safety feature.

 

[PeterN]

As soon as the unit turns its self on and try,s to keep you alive when it hits the water , all the alarms or protocols wont help ..

what you need is, if you don t do the full pre dive tests , then no dive. fall over board and the unit just free flows in to the tits and keeps you top side .

:rocker:

Billiant! I don't want one, but the best idiot defence method mentioned so far.

Peter

 

[Mark Chase]

Something that stops you diving without a canister would take serious suicidal tendencies, but what about alarms or protocols to stop you getting into the water without a complete system check being done, or where the system 'fails' but you 'know better'? (Sometimes the system fails but it is serviceable and so the user loses confidence in the system)

http://www.ccrexplorers.com/showpost.php?p=146569&postcount=208 (Functional Safety thread, post 208) onwards shows examples of people 'breaking the rules' and still going diving, and the potential reasons for this. Madness, until you are in that situation...

Regards

Obviously for divers who dont care that they will die if they dont dive a CCR properly?

Yes thers these types of systems on units like the Sentinal and Posiden, but obviously they are not fool proof and they are so unreliable it amazes me the owners ever get wet.

The Sentinal was a work arround button so you can ignore the failed pre dive checks and just go diving.

On both my Inspo Classic and My HH the pre dive checks failed costing me a day out and an expensive dive.

There was nothing wrong with the core function of my unit, it was a handset telling me I had a problem that didnt exist.


If you dive an automated unit you brain train that the unit will do it all for you and keep you alive.

If it dosen't you die, and thats whats hapened to several divers in the past.

If you dive a manual unit you know 100% if you dont do it propely, you will die. So you do it reguardless of a lack of a hand set telling you to.

Some fixes seem simple but they are not. Wet switches to automaticly acitvate the controlers?

All good but useless if the 02 is switched off. And yes people do miss the buzzers and flashing hand sets.

I had a unit with wet switches. The wet switches prevented the hand set being turned off. The hand set broke mid dive and decided to continiously inject 02 at 70-80m.

And of course, because of the wet switches, I couldent turn the damed thing off.

I had a perfictly good MAV and secondary PP02 display that was rendered useless by the "auto switch on" function of the primary controler.

Safety feetures can kill.

ATB

Mark

 

[Oldefors]

This ^ is Impossible.


Anything you try to engineer out can always be bypassed with stupidity, error or cunning, divers will always try to bodge a dive despite the danger, it seems inherent in Divers DNA (something for the next study Gloc?)

You could put 100sensors in and someone will work out how to fool them- wanna test the electronics on my Unamed future CCR with multiple scrubber sensors, just drop a can of warm baked beans in that fits the scrubber, gives off heat and CO2 long enough to boot through calibration- Job done :big:

If I was an engineer trying to outsmart your diver I would put a RFID reader in the unit and encrypted RFID chip on the scrubbers:

- Assure a scrubber is in place.
- Keep track of the usage time of the scrubber (store time on the scrubber chip).
- Make sure the scrubber is within best before date.
- Only scrubbers sold/approved by me could be used.
- You could prevent use of scrubbers from a faulty batch if the controller SW is updated.

I hope no one steals my idea, because I really don't want it myself :flip:

 

[Ben Field]

If I was an engineer trying to outsmart your diver I would put a RFID reader in the unit and encrypted RFID chip on the scrubbers:

- Assure a scrubber is in place.
- Keep track of the usage time of the scrubber (store time on the scrubber chip).
- Make sure the scrubber is within best before date.
- Only scrubbers sold/approved by me could be used.
- You could prevent use of scrubbers from a faulty batch if the controller SW is updated.

I hope no one steals my idea, because I really don't want it myself :flip:

How does the presense of a RFID chip confirm there is a scrubber in place? You'd need additional optical, weight, temp sensors to confirm existence and operations, your scrubber system already costs £2000, how much will the unit be? :haha:

 

[CFU]

How does the presense of a RFID chip confirm there is a scrubber in place? You'd need additional optical, weight, temp sensors to confirm existence and operations, your scrubber system already costs ***163;2000, how much will the unit be? :haha:

Well if you have pre packed scrubber...? The dive computer gets a unique id transmitted and after 3h of diving with that id it will warn you and not pass pre dive checks anymore... No scrubber in place no RFID chip so won't pass pre dive...

It would not be that hard and really not expensive with pre packed scrubber cartridges


Sent from my iPad using Tapatalk HD

 

[CFU]

I hope no one steals my idea, because I really don't want it myself :flip:

I think for pure type R or recreational rebreathers this would be something that could be acceptable... It's a decision you have to make before you decide which road you want to go down... For a tech type ccr this nothing we would ever like to see that's true... But I think we will also never see it, therefore training for technical units will always be more intense, expensive...


Sent from my iPad using Tapatalk HD

 

[Oldefors]

Well if you have pre packed scrubber...? The dive computer gets a unique id transmitted and after 3h of diving with that id it will warn you and not pass pre dive checks anymore... No scrubber in place no RFID chip so won't pass pre dive...

It would not be that hard and really not expensive with pre packed scrubber cartridges


Sent from my iPad using Tapatalk HD

Almost as I thought. I would save the usage data on the scrubber chip. And as the time limit is encrypted on the chip there is no point moving chips from one scrubber to another!

I've only used it in my proffession as an industrial automation engineer, and then as a escort memory system when machining engine blocks.


Perhaps that was what you meant as well... Keeping track in the dive computer only would make it easy to just switch scrubber with your buddy when getting close to the limit.

 

[MeRodent]

Almost as I thought. I would save the usage data on the scrubber chip. And as the time limit is encrypted on the chip there is no point moving chips from one scrubber to another!

I've only used it in my proffession as an industrial automation engineer, and then as a escort memory system when machining engine blocks.


Perhaps that was what you meant as well... Keeping track in the dive computer only would make it easy to just switch scrubber with your buddy when getting close to the limit.

Wouldn't even need to be RFID as a direct contact with a chip would work. They do it on inkjet cartridges in an attempt to stop people refilling. But then again the refill manufacturers produce chip re-setters to get around these.

 

[Oldefors]

Wouldn't even need to be RFID as a direct contact with a chip would work. They do it on inkjet cartridges in an attempt to stop people refilling. But then again the refill manufacturers produce chip re-setters to get around these.

I imagine it would be a poor idea using electrical contacts in that environment?