The Checklist Sticker

[GF99/99]

Ok, thank you for the translation I think I'll make my own sticker to dive my MCCR Triton.

Remember the Triton has an O2 MAV. And if you have the offboard kit then you have two of them.

 

[tbone1004]

This is the expanded version of "Ted's 2's". This is in addition to the OC checks, so bailout breathe would be on that side or if you use the "dilout" or since it is from Ted then "Bailuent" concept they would be covered under the Dil side checks.
Gas-Dil/O2
Loops-Negative and Positive check
Add Valves-O2 MAV, Dil MAV, *may be 3 instead of 2 if you have an ADV*
Inflators-BC, Wing
Displays-Handset/HUD *may be 1,2, or 3 depending on your unit*

We can argue the merit of prebreathe in a different discussion, but the 9 definitely fits perfectly on the battery compartment so no objections there. I don't dive a Shearwater so I won't be able to steal them as they won't work with the Freedoms unfortunately, but I'm definitely going to pass these on to some buddies

 

[doctormike]

This is the expanded version of "Ted's 2's". This is in addition to the OC checks, so bailout breathe would be on that side or if you use the "dilout" or since it is from Ted then "Bailuent" concept they would be covered under the Dil side checks.
Gas-Dil/O2
Loops-Negative and Positive check
Add Valves-O2 MAV, Dil MAV, *may be 3 instead of 2 if you have an ADV*
Inflators-BC, Wing
Displays-Handset/HUD *may be 1,2, or 3 depending on your unit*

We can argue the merit of prebreathe in a different discussion, but the 9 definitely fits perfectly on the battery compartment so no objections there. I don't dive a Shearwater so I won't be able to steal them as they won't work with the Freedoms unfortunately, but I'm definitely going to pass these on to some buddies

Thanks!

Of all the things to do, the one thing that I don't think that there should be controversy about is the prebreathe. If you do nothing else, you should do that. If your CCR can't sustain a PO2 of 0.17 for any reason, you definitely want to black out on the dive boat and not in the water.

The one controversy over prebreathe - to my understanding - was that it was originally recommended as a way to detect hypercapnea, and as you know, @Dr Simon Mitchell showed us that a 5 minute prebreathe won't necessarily do that. But it can definitely demonstrate a failure to maintain a breathable loop.

As far as the Ted's 2s version, I am always concerned about list items being anything other than an explicit description of what you need to do. Once you start putting items one mental step away, once you are relying on memory at all (like with a mnemonic) there is a chance for error.

To take this example, by using the term "Gas", you are introducing some ambiguity. You may turn on the valves, assume you have checked that box, but your CCR may not be delivering gas (empty tank, first stage issue, etc..). You may check your SPG, but the valve may be off and the line pressurized. The best way to do a checklist, in my opinion, is to have the actual taks in non-ambiguous language. (1) Tank valves on (2) Check SPG. The checklist is specifically meant to back up the vagaries of human memory.

Also, I haven't been in the habit of doing a negative and positive test as part of the pre-splash check, when I'm in the unit. Does Ted recommend that? I guess it's not a bad idea, it's possible for a leak to occur between the time you check it on the boat or at build, and the time you put it on. But at least a flood will be something that you would be aware of and you would be able to bail out if necessary (hopefully with enough buoyancy), unlike hypoxia.

And finally, I think that a pre-splash checklist needs to be unit-specific. These are cheap and easy to customize, no need to take up valuable layout and cognitive real estate with questions about how many displays or MAVs your unit has.

 

[tbone1004]

@doctormike prebreathe for ppO2 is one thing, but with the solenoid you can wait to hear it click up to setpoint and on a CMF the flow check is part of setup but you can also hear it. Depends on schools of thought but it's definitely not for hypercapnia. You can do that between the negative and positive check. My positive check is done with O2 only so I can perform calibration verification of the cells. With a mCCR you can just let the leaky valve fill the thing up, and with an eCCR you can tell it to go to high setpoint and it will click itself up which validates function of the automatic O2 addition. Starting with a unit full of O2 also means that you can easily get your 1.6 check at 20ft so it's a pretty efficient way to get a lot of things done at the same time. Huge thanks to @Bobby for that one!

With the 2's, everything is basically in pairs, so when you talk about "gas" it's to remind you to check the bottle. If I have to spell out everything that has to be done with that bottle, it needs to be on a full checklist and not what is essentially a "pre-jump card".

 

[doctormike]

@doctormike prebreathe for ppO2 is one thing, but with the solenoid you can wait to hear it click up to setpoint and on a CMF the flow check is part of setup but you can also hear it.

I have never heard my solenoid, except with the head out of the unit on the bench. Presbycusis. And of course, clicking doesn't mean that you have a breathable loop!

Depends on schools of thought but it's definitely not for hypercapnia. You can do that between the negative and positive check. My positive check is done with O2 only so I can perform calibration verification of the cells. With a mCCR you can just let the leaky valve fill the thing up, and with an eCCR you can tell it to go to high setpoint and it will click itself up which validates function of the automatic O2 addition. Starting with a unit full of O2 also means that you can easily get your 1.6 check at 20ft so it's a pretty efficient way to get a lot of things done at the same time. Huge thanks to @Bobby for that one!

Not sure I understand - between the negative and positive check? Seems compliicated. What's the advantage of that over just breathing it for 3 minutes to see if it will hold a PO2 of 0.7 while you are on the loop? I mean, that's what you want to confirm, right? This doesn't sound like this approach is confirming that specifically.

Are you doing this while you are wearing the unit, just before splash? Is that when you are doing positive and negative? Maybe I wold understand better with a list of what you are recommending...

With the 2's, everything is basically in pairs, so when you talk about "gas" it's to remind you to check the bottle. If I have to spell out everything that has to be done with that bottle, it needs to be on a full checklist and not what is essentially a "pre-jump card".

Gotta disagree with that approach. A good checklist shouldn't remind you and then depend on you remembering an association, that's a mnemonic. It should tell you a task explicitly.

Are you saying that there are so many steps to remember, that you can't use a checklist because it would have too many critical items? If anything, that signifies a greater need for a checklist, not a reason to lump steps together.

And of course, this resource is about the pre-jump checklist. None of these take the place of a build checklist - that's a different thing. Before jumping, the only two things to do with the bottle are to open the valve and check the SPG. You aren't analyzing your gas after you have donned the unit...