Remember when you started with Rebreathers.

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

They actually would have been negative tests, not positive tests, since the SF2 can't hold a positive to any sort of useful degree. I did notice that though and was wondering why I checked + rather than -. I really just need to remove the + test from the checklist.

So doubling down, I skipped a step AND marked the wrong one!

Really, I'm using it the same way you do, follow the steps and take notes. I was clearly being lazy about actually checking the boxes. I would certainly stop the check if I came across a problem.

But to clarify, if you were using my list above and during the dil MAV check, you noticed a slight leak from a hose that needed an O-ring replaced, you would start the whole list over again? Or would you just address the problem before moving onto the dil side?
 
Or would you just address the problem before moving onto the dil side?
This.
The checklist completion just stops when you hit a block. It resumes when you've fulfilled the checklist item.
Thanks for clarifying!
 
I've shared these before, a quarter sheet that removes the obvious steps like "connect bottles," while leaving a few less obvious ones which are still a little obvious, and leaves me space to document values. I converted this to a Jotform version but at most caves I don't have signal, the benefits with electronic log is I can save to .xls and see how values change over time.

And I have a business card size that remove the ability to record values and summarizes even further.

And the sticker on my controller on both sides which summarizes even further.

At the end of the day, I will be honest, that I don't fill out my sheet of paper as often as I wish. A laminated version with a dry erase that I could photograph might be a better idea, but I'm sure I'd lose that marker as often as I lose my pen. I use the business card as a reference.

I do check my gasses, but if I'm doing a week of diving, I don't check my dil and o2 and dilout and all for o2 and co daily, I just confirm those when filling tanks. I look for oddball numbers on mv, I check voltage values, I don't calibrate that often. I know if my loop is clean and EAC direction only matters if you are going to use the same EAC later, which I rarely do. I can make sure stuff is connected with that prebreathe and positive and negative. I often shorten the prebreathe to just enough to get the solenoid to fire and cells to respond. The DSV direction check is not as critical as you would think, if you have it backwards, the lever will be in between your eyes, very noticiable.

I don't know about diving a rebreather that won't hold a positive and negative. Optimas seem to hold them fine.

What is super critical is that whole not turning the O2 off thing. It's easy to forget. I am still planning on putting a Vindicator knob on that tank and asking boat crews to check it before I jump. I think often of that poor gentleman who passed because he forgot his oxygen leaving behind a wife, and I myself forgot once, I noticed it while prebreathing on the surface at Martz. I swear I will never forget again, that red light on my HUD was my come to jesus moment with oxygen valves.

Is the choptima your first rebreather or are you just transitioning? I do feel that it's a little easier to dive with aluminum tanks, but steels hold more gas and gas is life.

optima quarter sheet.png
optima card.png
 
As I now understand it:

It only counts as “using a checklist,” if you address each item on the list. Partial verification or mental lists will not cut it for most.

Dive Rite has four, mutually supporting Optima CM, checklists (CL) on their website. The Assembly Guide CL has 31 items, verifying/documenting gases, sensor performance, calibration, pressures, and equipment checks. It is intended to be written on and serves the purpose Rose highlighted. Survival CL and Preflight CLs are the two critical ones for me. They follow for your edification.


Survival Checklist
Confirm scrubber media, bore plug, and premix tubing O-ring’s are correctly installed
Confirm diluent and oxygen cylinder contents and pressures
Inspect DSV mushroom valves and conduct positive and negative checks
Check internal and external voltages and mV readings in air
Complete the Preflight Checklist before diving

Preflight Checklist
Turn cylinders on, ensure in-line shutoffs are on, verify pressures
Confirm ADV function, check manual add valves
Verify handsets/HUD
Prebreathe, verify set point, confirm PO2
Confirm BCD/Dry suit functions
Don/verify operational use of bailout – check pressures
Perform bubble check

Correct usage of these checklists would have prevented the vast majority of CCR fatalities I looked into. The non sequitur is why did/do intelligent, accomplished, divers die rather than use checklists or prebreathe their CCRs? Survivors also wonder. Rebreathers are exotic lovers. Expensive, high maintenance, temperamental, not for most, but capable of providing wonderful experiences. Treat them poorly, ignore them, skimp on their needs, and they will hurt you. Continue the abuse and they may try to kill you. Treat them well and they can just barely kill you.

My only advice. Always prebreathe the unit, because, "All skill and preparation is in vain when an Angel pisses in the flintlock of your musket."
 
mccrlst1.jpg
mccrlst2.jpg

I like simple. Here are my checklists for my home-made unit.
 
The checklist completion just stops when you hit a block. It resumes when you've fulfilled the checklist item.
I dive a Poseidon Se7en+ which notoriously goes through an automated pre-dive checklist. If any of the 50+ steps fails, the checklist is aborted, and must be resumed from the beginning once the original problem has been addressed. Personally, I find this approach preferable, as fixing something may potentially create a new issue that didn't exist before.
 
I dive a Poseidon Se7en+ which notoriously goes through an automated pre-dive checklist. If any of the 50+ steps fails, the checklist is aborted, and must be resumed from the beginning once the original problem has been addressed. Personally, I find this approach preferable, as fixing something may potentially create a new issue that didn't exist before.
Arrgh! That would make me crazy!

And without having thought your last comment through fully, it strikes me that if fixing something changes a step higher in the checklist, then your checklist is in the wrong order.
 
Really depends on what the issue is. Test drysuit inflator, hose didn't get connected or the bottle turned back on does not require starting at the beginning of the list. Pause that step, fix, continue. Having to pull the unit apart to do something inside, that is a start over event.
 
if fixing something changes a step higher in the checklist, then your checklist is in the wrong order.

It could be. But if I change an o-ring because it failed the positive pressure test i am violating the integrity of the loop, and i would rather do both positive and negative pressure tests again rather than positive only, for example.
I used a JJ before the Se7en, and I really liked it. I was really worried about the automated check list when I changed rebreather, but it grew on me. I still have a manual assembly checklist, a pre-jump checklist and a disassembly checklist, all on laminated paper. I don't think that the automated check replaces the manual lists, but it removes some of the risks related to the human factor, so i don't think it is a bad idea.
 
https://www.shearwater.com/products/perdix-ai/

Back
Top Bottom