Checklists in Rebreather Diving

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The few pre-jump checks are simple and memorized (O2 valve on, gauges look good, PO2 ok, inflators/mavs).
Please watch the video. The docors in that study weren't stupid or incompentent. The checklist is to make sure you don't forget stuff that can kill you. Has happened to other people... people do get distracted and do get killed, we know that for a fact. If what's in the video doesn't make you want to use a list, I don't know what would. The numbers are pretty clear and I reckon the average surgeons is smarter and better trained than the average diver. They also thought the could memorize stuff but they did much better with the lists.
 
What about mnemonic checklists, like you do when DiveMASTERing -- BWRAF. Other's use GUE-EDGE. Others maybe use a physical representation: spectacles, testicles, wallet and watch...

Checklists aren't all written documents.
The value of using written checklists has long been recognized in aviation. In fact, I wouldn’t be surprised if the whole concept of diving checklists was basically borrowed from flying. There is a ton of research into the psychology of flying, and a lot of it applies to diving. All pilots – from PPL to ATP to military – are drilled to use them.

The big danger is running through checklists by rote, mechanically, without investing one’s brain in every step – and yes, it still happens, in spite of all the training, with sad consequences. My observation, the safest pilots are almost autistic. Since I’m not, throughout my years of flying and now diving, I’ve tried to cultivate the skill of ‘single-tasking’ – totally dedicating my brain to the specific sub-task in hand, excluding distractions. A complimentary skill is then juggling these sub-tasks while still keeping together a coherent picture of the mission, this is usually a function of experience. By the time a diver reaches the CCR phase, they should pretty much self-select for either having this ability, or a keen intent to grow it, imho

In flying, in addition to checklists to cover all flight phases and contingencies, there is also a concept of ‘memory items’ – actions that need to be taken first thing, usually in an emergency, before a checklist can be reached. There are also mnemonic checklists that are basically useful heuristics for situations when pulling up a written checklist is going to create a distraction – GUMPS on final, etc. In that sense, I see nothing wrong in having a memorized list of critical pre-splash items, pretty much the way @Wibble describes. As long as you are invested in it, every step of the way
 
I have a pre-splash sticker on my handset. I’ve found it helpful. And no need to go digging in my pockets.
 
Please watch the video. The docors in that study weren't stupid or incompentent. The checklist is to make sure you don't forget stuff that can kill you. Has happened to other people... people do get distracted and do get killed, we know that for a fact. If what's in the video doesn't make you want to use a list, I don't know what would. The numbers are pretty clear and I reckon the average surgeons is smarter and better trained than the average diver. They also thought the could memorize stuff but they did much better with the lists.
If you look at my posts in this thread I have been arguing the case for systems that account for human fallibility, and advocating for checklist use. I do use a detailed checklist every time, and admitted in that very post that I probably should formalize my SECOND checklist (the pre-jump). A little sticker is a good idea for that one.

The notion of diver intelligence or experience keeps being brought up in this conversation. I think it's irrelevant here. There are plenty of very smart, experienced divers who died on CCR because they got complacent - and plenty of idiots and newbies who survive just fine because they are always diligent. And vise versa. Human nature, the capability and the fallibility, exist across the board.
 
- and plenty of idiots and newbies who survive just fine because they are always diligent.
or just dumb luck.

BTW: IIRC you one of the people that claim it takes too much time to pre breath.
 
The value of using written checklists has long been recognized in aviation. In fact, I wouldn’t be surprised if the whole concept of diving checklists was basically borrowed from flying.
Absolutely. Which is why I've my build and closed checklists from when I started diving CCR.

The build is (relatively) long and complex. It needs to be done in order and properly. Writing down the analysis, pressures, milivolts, cell checks, etc. Even the weights.

If you look at my posts in this thread I have been arguing the case for systems that account for human fallibility, and advocating for checklist use. I do use a detailed checklist every time, and admitted in that very post that I probably should formalize my SECOND checklist (the pre-jump). A little sticker is a good idea for that one.

The notion of diver intelligence or experience keeps being brought up in this conversation. I think it's irrelevant here. There are plenty of very smart, experienced divers who died on CCR because they got complacent - and plenty of idiots and newbies who survive just fine because they are always diligent. And vise versa. Human nature, the capability and the fallibility, exist across the board.
For small checks of a very few steps, it's perfectly acceptable to use a mnemonic, or count, or touch (if you learn like that).

The pre-jump check needs to be done very quickly and one-handed (as you're holding on to the boat/scooter with the other hand).
  • Drysuit: dump, inject
  • Wing: short inflate
  • Gas: diluent inject, oxygen inject
  • Monitor: PPO2 OK, gas pressures OK (AI)
 
or just dumb luck.
It's not luck when you're diligent.

One of the benefits of a Manual CCR is it forces you to be aware of your PPO2 at all times as you need to predict when to inject.

Whilst an E-CCR is good, you won't need to be as diligent because the computer will sort it out. Until it doesn't.

When you've a Hybrid CCR (Manual with Electronic backup), then you will get the "hiss of shame" by the solenoid which says you weren't looking out for the PPO2 and you need a good kicking for being so delinquent.



@berndo - what box do you dive and where?
 
dumb luck also applies across the board and kills renowned tech divers
So what? The point is that 'doing a checklist in your head' and skipping pre dive checks have killed people. People who cut corners are more likely to die diving.
 
or just dumb luck.

BTW: IIRC you one of the people that claim it takes too much time to pre breath.
Just to clarify, he and I never said it takes too much time to pre-breathe. The point was in order to get an effective prebreathe, 5 minutes is not enough. So in my opinion (not speaking for him), I can accomplish the same thing with a quick predive prebreathe to insure unit is working properly, cause I'm not doing 15 minutes.
As for checklists, I should maybe clarify my opinion. I definitely agree checklists are important. Being in a medical field we use checklists and they are beneficial. I read Atul Gawande, MD's book "the checklist manifesto" many years ago and between that, my medical background, and my flying background, I believe in checklists. But I also believe checklists can make many people complacent. I see it all the time at dive sites. People sitting in the water with their checklists, one buddy in never never land paying no attention. I use a checklist for build and calibration. For final prejump, it's a memorized checklist that has been simplified down to checking valves, checking all things that flow gas flow gas, and bov check. Its very simple and my buddies and I have done it the same way for 4 or more years now. It works on boats and it works floating in the run at Ginnie. The "memorized checklist" also flows almost identically to my prejump checklist in doubles, except with a little extra steps. It makes it easy to follow and remember, and for me and my buddies we're not zoning out reading a sheet of paper. It forces you to use your mind.

I know very well there are many, many studies that say use a written checklist at all times. And I do up until jump. But I'm also very paranoid about being that person not turning on gas, so it is a major focus of the prejump mental checklist. I accept the potential downsides of a nonwritten list and they are within my comfort range. My personal opinion based on experience is that I do better with a mental in-water, pre-jump checklist.
 
https://www.shearwater.com/products/perdix-ai/

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