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lermontov

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with a revo on with RMS theres a time lag to wait for the scrubber to warm up and indicates when its ready to go- thats enough time to spot a PO2 drop - Id imagine theres a reason a checklist is done in a certain order and thats probably one of them.
 

stuartv

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with a revo on with RMS theres a time lag to wait for the scrubber to warm up and indicates when its ready to go- thats enough time to spot a PO2 drop - Id imagine theres a reason a checklist is done in a certain order and thats probably one of them.

Yes, there are several steps in the checklist that should reveal the problem, if you skip the step of turning on O2 - and then proceed on to the other steps. Steps like "verify O2 button on MAV is working" and "check O2 pressure". And then, as you say, the pre-breathe. And "verify ppO2 of 0.7 or higher." Any one step might not catch it. But, if you do them all, you would be very hard-pressed to miss that O2 was off.

The prior steps, for the dil, would ensure the loop ppO2 was pulled down below 0.7. So, failing to turn the O2 on means the subsequent steps will tell you that O2 is off - if you are paying attention at all.

That is one of the things I appreciate about the design of the rEvo factory checklist. It seems well-designed to not just make sure you're safe to dive, but also to ensure that if you miss a step, a later step will reveal your error. To the extent it can, anyway.

I would really love to see an analysis of CCR checklist designs by a human factors expert like Gareth Lock or similar. My intuition is that the rEvo checklist would be deemed "well designed" and some other units' checklists would be deemed "not so well-designed" in comparison.
 

stuartv

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with a revo on with RMS theres a time lag to wait for the scrubber to warm up and indicates when its ready to go- thats enough time to spot a PO2 drop - Id imagine theres a reason a checklist is done in a certain order and thats probably one of them.

Also, just for the record, with rMS the pre-breathe generally takes 1 - 2 minutes. If you don't have rMS, then the prescribed pre-breathe is 5 minutes. So, with or without rMS, you should catch it if you fail to turn on the O2. Assuming you are putting any effort at all into following the pre-jump checklist.
 

Whitrzac

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I think he has looked into it and talked about it in his book, and a very large majority of RB divers that died were not using checklists.

After 100+hrs on mine, I don't think I've seen anyone use a physical pre jump checklist.
 

Wibble

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Why are you implying that you can't check the ADV with the O2 on?
Just like to follow the checklist.

Typically the diluent and suit inflate can be turned on whilst the unit's still tied on to the boat. Once untied, need to climb in before everything falls over as the boat rolls about. I kind of like going from left to right and getting into the unit with the bailout stages either side of me.

Turn the O2 on after faffing around getting into the unit, putting the controller on my arm, changing the setpoint from 0.19 to 0.7 (although a hypoxic mix will be triggering the solenoid as soon as the Petrel's turned on). Normally use the pre-breathe to get the Kubis on.

Yeah, it's all horses for courses. And calming before the jump.
 

Wibble

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I would really love to see an analysis of CCR checklist designs by a human factors expert like Gareth Lock or similar. My intuition is that the rEvo checklist would be deemed "well designed" and some other units' checklists would be deemed "not so well-designed" in comparison.

Have re-done the Revo build and close checkllists as a double-sided A5 (that's half a letter). Use this on every build and write down the cell voltages, etc. Becomes a written reference to show how the cells are; gasses used, etc.

The factory checklist docs does not have the check-boxes nor space to write pressures, voltages, etc.
 

stuartv

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I think he has looked into it and talked about it in his book, and a very large majority of RB divers that died were not using checklists.

After 100+hrs on mine, I don't think I've seen anyone use a physical pre jump checklist.

I have over 100 hours on mine. I still use the hard, engraved physical checklists on every build and every jump.
 

broncobowsher

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I have over 100 hours on mine. I still use the hard, engraved physical checklists on every build and every jump.
I need to check, but probably just under the 100 hour mark. But I use the checklist every time as well. Just slightly revised. I got new cards laser etched. The biggest thing was going from gauges to transmitters. The generic checklist cards are good in general. If not jumping from a boat, or modified from stock, it just needs a tweak.
 

cathal

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That is one of the things I appreciate about the design of the rEvo factory checklist. It seems well-designed to not just make sure you're safe to dive, but also to ensure that if you miss a step, a later step will reveal your error. To the extent it can, anyway.
I would really love to see an analysis of CCR checklist designs by a human factors expert like Gareth Lock or similar. My intuition is that the rEvo checklist would be deemed "well designed" and some other units' checklists would be deemed "not so well-designed" in comparison.
I am diving a rEvo since 2013, I work in operational safety management. Regarding the rEvo build checklist I am not a fan having read this book on checklists.
Two key recommendations when it comes to safety critical checklists are that firstly, they should be in your own words and secondly, they should be interactive i.e. that you have to manually tick off each step of the build as you complete it. This second part obviously does not apply to the pre-jump list.

Regards
 

broncobowsher

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I am diving a rEvo since 2013, I work in operational safety management. Regarding the rEvo build checklist I am not a fan having read this book on checklists.
Two key recommendations when it comes to safety critical checklists are that firstly, they should be in your own words and secondly, they should be interactive i.e. that you have to manually tick off each step of the build as you complete it. This second part obviously does not apply to the pre-jump list.

Regards
But still better than none, which is more typical.
 
https://www.shearwater.com/products/swift/

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