Rebreather setup and tear down time?

Jimmer

So I've heard all the horror stories from OC people, about how it takes a million hours to prepare your rebreather, and another 4 months to tear it down to clean it (a minor exageration, but you get the point). Obviously there is more setup and maintenance time than with OC, but just how much are we typically talking here?

Thanks,
Jim

PhilSiswick

Hi,

It's not as bad as the doomsayers would have it. I'm pretty inexperienced and therefore haven't prepped my unit that much, but I'd say (for my Vision) it works out roughly as follows:

- A few days before I'm due to go diving, I set the unit up, run positive and negative checks and do a calibration. That means that a) the unit is pretty much ready to go and b) I know that it is working. That all takes about 60 minutes, about 50% of which is spent setting up and/or packing other gear while the pos and neg tests 'run'
- Before each dive, it probably takes about 5-10 minutes longer to get kitted up and ready to go because of the calibration (if needed) and system checks. That's easily balanced by not needing to get as man fills
- Each evening (or every second evening depending on dive time), about 15-20 minutes to change the scrubber and take the head off to dry

That's pretty much it. Everything else is just as for OC, in my experience.

Hope that helps.

Cheers,

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Phil

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lizardland

About ten minutes to fill, I like to have a quick check over the guts of it as I'm doing it. I switch the displays on while I've got it open so the cells are reading air and check the reading. Reassemble with cylinders, 3-4min(?), negative check 30s, check cells with an O2 flush (also checking operation of O2 valve at same time), maybe another minute. If the O2 and air readings are OK then no need to calibrate. Calibration is only a few min if needed. Check DSV flow, 2 or 3 breaths, positive check, about 10min but that's 10min that you can be doing something else. It's generally the last thing I do. I'd say 20min prep the night before the dive.

A few checks before the dive, maybe a couple of minutes, about the same as a normal; kit check on OC. Cleaning? Yeah, right...

The time comes in fault finding if you get a problem. That can be really painful.

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diverreb

It does take a bit more time to set up & clean than OC, depending on which unit you buy, that time will vary. I dive an O2ptima and I'd say I spend an hour to an hour and a half per dive day more than OC between set up and cleaning of the unit.

But you have to also look at the time saved... Filling tanks & switching tanks during dives.

If you are getting three long dives off a set of 20's that take about 10 minutes to fill vs filling 3 sets of doubles and 3 - 6 deco bottles the total time invested more than evens out. Granted you fill bail out bottles, but for the most part that's a one time deal.

If you have to go to a dive shop to fill the doubles and deco bottles then that really adds to the time line.

Richie

JCdesign97

The million that people talk about are actually in dog hours, so multiply by 7 ...

All good points made above about the time trade-offs, etc.; and of course as you get more experience with whichever unit you select you will streamline the processes. The bottom line is a diligent diver (OC or otherwise) would have already been spending X amount of time prepping/checking his or her kit. One who isn't in that category probably shouldn't be considering a Rebreather in the first place ... JMHO.

__________________
Cheers,

John

jhaaja

Setting up before going to the dive site takes 15-30mins, depending on if I have to fill tanks or lime.

After days diving it is 5-10mins and the unit is rinsed and ready to wait for new adventures

jkaterenchuk

I have never dove doubles so take my comments with a grain of salt but here are some of the things I have observed while diving CCR on a boat with most others diving doubles that really should be accounted for in any discussion of time.

1) It so nice to be able to offer your help between dives to all the OC divers that are busy bumping into each other while changing tanks in rough seas.

2) It nice to be able to help all the OC diver load their gear back into their vehicles at the end of the day since yours is already loaded.

3) Its nice to be able to provide some extra room for the OC divers to secure their gear on the boat since your takes up less space.

4) Its nice to be able to show up at the dock 15 minutes before departure and know you won't be holding everyone else up from departing.

John

Dave IR

I allow 1 hour for a complete re-build from all the parts dismantled and cleaned. This 1 hour includes:
1) Dil and O2 bottle fills
2) Scrubber fill
3) inspect parts, lube & assemble
4) unit checks and calibration
5) pack, ready for journey to boat.

This is for my Sports KISS and my procedure/routine has resulted in zero dives lost due to unit failure in over 100 hours use.

I think the fact that the unit is so simple and easy to tear down / set up allows every major component to be cleaned, inspected and prepared before every dive day in a very efficient manner.

For tear down / clean it takes me about 20 mins. This includes full anti-bac cleaning. I do this every dive day.

Maybe I take too long & do too much, but it works for me.

RichClark

I'd say my timing are pretty much the same with my Classic KISS. I tend to take my time and prep my unit when i'm not in a hurry.

Cheers

Rich

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Dave IR

I'd actually say it is a bit quicker on the CK as the unit doesn't have to be pulled apart as much as the SK.
Thanks to my shinny new S/S CK case getting those pesky lungs off and on is a lot easier than the original ali case

But as you say - whats the rush...