Checklists in Rebreather Diving

[solside1971]

Dear All,
I'm quite a Newbie in RB diving and own a rEvo. rEvo has 3 checklists: 1) a built checklist where you follow steps to assemble your unit, 2) a closed check list where you check your unit when you have assembled it and of course prior to diving, incl. calibration and 3) a pre-dive check (just before you jump into the water.
When I did my RB class, my instructor briefed me on how important those lists are and that you should respect them. As I'm a OC DIR diver (mostly GUE), I'm used to follow a certain preparation line before I jump into the water and I'm also rather organized. Consequently I still follow all those lists, which means that before diving, I also calibrate the unit, etc. However, I noticed when I go diving with other RB divers, that they do not really follow the lists, i.e. not always calibrate, but calibrate just before a trip, just do the negative check and the sensors, and also do not really pre-breathe 5 minutes, but just a while when they walk down to the water. I also noticed that the instructors do not really do this even though they have students or do dives with former students. And instructors have been to me usually a kind of role model, who should themselves do what they "preach". Ok, as a newbie you might be really "obsessive" with details and still do not have the complete routine or might not be yet capable to evaluate the specific details under water (i.e. to "interpret" the millivolts according to the PO2 and you do not do it everyday, and the instructors or more advanced people have much more knowledge and know their unit more intimately. I must admit it often gives me a bad feeling, like if I'm "retarded" or too slow etc. and all the others have to wait for me, but on the other hand I would like to trust myself and prepare well, be sure about my equipment...

So I was wondering how you do see this? Thanks!

 

[Marie13]

I’m a new CCR diver as well (Kiss Spirit). I follow a checklist and calibrate. So far I’m doing day trips, so my unit is getting set up at home. All I’m doing at dive site is pre-breathe.

 

[davehicks]

Checklists are great and good to have available, especially if you get distracted or interrupted "mid-ritual". Eventually you develope sort of a routine or ritual that you can repeat reliably, and you pare it down to essentials. Pos-neg and drain the loop every dive, but don't calibrate every dive. If you see an anomaly when getting ready, add the calibration back in. I typically calibrate when i set my unit up, using the dregs of my previous dives O2 bottle. Then i put on a fresh bottle and check the pressure. Pre breathing for 5 minutes is bullsh@t.

Here is my pre dive checklist:

Kiss Sprit Checklist
o Drain Loop
o POS / NEG Test
o OPV Open 3 Clicks
o O2 Pressurized
o Straps – Lungs, Chest, Crotch
o Stage Bottle – Offboard Connected
o Stage Bottle – Drysuit Inflator
o Breathing Loop – Test O2 MAV
o Breathing Loop – Breath BOV
o Breathing Loop – PPO2 0.7
o BC Wing – Inflate / Deflate

 

[kissonerga.ccr]

If you are obsessive about following all the checklists, and taking your time to do it, you will likely have fewer friends. But you will also likely have a longer diving career

 

[broncobowsher]

I ended up revising the rEvo checklists. The generic checklist did not match my build. Don't have DREAMS or RMS, but I do have transmitters.

As for following the checklist exactly, not always. I may not cal. Often just verify that things are still good, but not the full cal. If they were all good the dive before, why change? If a sensor starts to drift, it is easier to notice if you are not always forcing it back into place with repeated cals.

walking pre-breath? Why not? Don't remember any instructions that you have to remain motionless during the pre-breath.

The lists are good. The pre-jump (actually walk in) I caught 2 issues. The latest was the line off the manual add block became disconnected in transit between build and jump. Before that I had an inflator that was disconnected after build (I screwed that up using the inflator to vent the drysuit bottle to get the regulator off but didn't reconnect). Both times the lists worked to detect the problem before the dive started.

 

[formernuke]

I do my pre-breath when shore diving walking in, did it during my class.

I also have more through checklist given to me by a friend.

 

[azstinger11]

We created an enhanced checklist from the factory checklists with some minor adjustments for changes in configuration and added spots to annotate the observed values. We then print and fill out new ones for each closed/build check we do. This allows us to monitor changes in things like cells, batteries, etc. We use the factory jump card however.

 

[rddvet]

. Pre breathing for 5 minutes is bullsh@t.

Thank you. I've been saying for years prebreathing is BS. I don't think it gives me any metric of importance. (I"m sure somebody will disagree and I don't care).

I use a checklist for build and calibration. I don't use a checklist for pre-dive at the dive site or right before splash. My buddy and I have a very specific routine that we go over together. I rarely dive with other people on ccr, but I still wouldn't use a dive site checklist. Once my unit's built, all of the checks are pretty common sense and are also part of my OC pre-dive checklist (obviously not exactly the same) such as valve drills and whatnot.
I'm sure some people will say checklists 100% of the time. IMO too many checklists shut people's brains off and they're just blindly following a checklist.

 

[wetb4igetinthewater]

I'm in the same boat being new.

I just show up early to the dive site early where I do my onsite calibration. Early on, I was giving the cheapo A-something sensors that would fail pretty badly. between when I did the at home calibration and on site calibration. That skunked a lot of dives. Make sure you don't have sh!tty a$$ sensors. As soon as I switched to sensors all from DGX, those problems went away.

 

[davehicks]

I'm in the same boat being new.

I just show up early to the dive site early where I do my onsite calibration. Early on, I was giving the cheapo A-something sensors that would fail pretty badly. between when I did the at home calibration and on site calibration. That skunked a lot of dives. Make sure you don't have sh!tty a$$ sensors. As soon as I switched to sensors all from DGX, those problems went away.

I have always had good results with DGX sensors too. Where were you buying the bogus sensors from?