Technical diving with oc versus ccr gas requirements

[ChuckP]

Cue why I dive a rack when in the ocean as the double 50's give me more than enough to get there.

Tom - what's this mean?

 

[kensuf]

Cost of gas is a huge factor for people diving a lot.

I think that's overstated if you're living in ConUS. Locally I can buy 18/45 for $0.52/ft3, that's roughly 20-25k cubic feet of gas before breaking even on the CCR and training, but not including cost of sorb and other consumables.

 

[broncobowsher]

Some destinations a CCR is the only option.
Bikini, they simply cannot bring enough Helium for open circuit. The trip is 100% CCR.
Truk, if you are doing the tech stuff Helium is nearly $5 a cubic foot. If they even had enough Helium the bill for a single trip would be the cost of a rebreather.

 

[kensuf]

Absolutely and that comes back to the logistics advantage of a CCR. However, for weekend warriors diving in ConUS, that's over 100 trimix dives before you begin to come close to the break even point.

Look, my bank account and I would love nothing more than for dozens of people to buy Fathom rebreathers and select me as their instructor. But cost savings for a fill are not one of the reasons they should use in their decision matrix on whether or not they should go CCR.

 

[ChuckP]

I think that's overstated if you're living in ConUS. Locally I can buy 18/45 for $0.52/ft3, that's roughly 20-25k cubic feet of gas before breaking even on the CCR and training, but not including cost of sorb and other consumables.

I heard $5/ft north of Chicago, not sure what the cost is around the great lakes area. Florida at Force E was I thought $1ish. Here in Cozumel it's 4ish, not sure what it is in Tulum.

I was looking at CCR training to go to Truk and Bikini on an extended vacation - I can't find the gas prices there but I thought I remembered 3k for a ten day trip was to be expected in Bikini.

That was my understanding of it - you guys dive it and are writing the checks!

 

[kensuf]

If you're going to Truk or Bikini, which is a "trip of a lifetime" event then yes, a CCR might make some sense. I'm supposed to be going to Bikini in 2022 myself, I will definitely be bringing a rebreather with me if the trip still flies.

 

[GF99/99]

To stir the pot a little more, there is the BOB (Bail Out Breather). Instead of taking open circuit for a bailout you take a second rebreather.

Oooo yeah now your really stirring the pot. Currently in the process of getting setup to play around with this with a Triton. Just about the order the unit next month.

 

[helodriver87]

Hardly worth the trouble and expense of a CCR and associated training - no? Unless kensuf's criteria are used

Well, keep in mind that you now have loiter time. This is more specific to overhead diving, but say you plan a triple stage dive somewhere way back in a cave. You get there on OC and you have a few minutes to look around before hitting turn. On CCR, you get there and you have all day (figuratively, you're still limited by O2 and scrubber). As long as you stay inside your bailout range, you can poke around as much as you want. Detours on the way back are also easy as long as you're watching your deco and O2 pressure. There's way more time to work in remote places.

 

[DiveTucson]

I think that's overstated if you're living in ConUS. Locally I can buy 18/45 for $0.52/ft3, that's roughly 20-25k cubic feet of gas before breaking even on the CCR and training, but not including cost of sorb and other consumables.

Damn...Helium in AZ/CA and other west coast states at a shop is around $2-3.50 per cubic foot. This adds up quickly when doing a 60M dive on 18/45 in doubles vs filling a diluent bottle.

 

[grantctobin]

I heard $5/ft north of Chicago, not sure what the cost is around the great lakes area. Florida at Force E was I thought $1ish. Here in Cozumel it's 4ish, not sure what it is in Tulum.

I was looking at CCR training to go to Truk and Bikini on an extended vacation - I can't find the gas prices there but I thought I remembered 3k for a ten day trip was to be expected in Bikini.

That was my understanding of it - you guys dive it and are writing the checks!

$0.08/L O2, $0.20/L He on Truk Master summer 2019. You pay for the bailout He fill independent of usage. Keg of sorb was $250 or $300. Square profiles and not reaching deeper than 180' doesn't add up to much dil usage and there's a number of dives on the Saratoga which were in the 120ish' avg depth range. Boat had 16/40 banked. My CCR bill was cheaper than those that dived the trip on OC on air+50%+O2 (oddly half the boat). Caveat this was on a 7 day trip and not the 10 day.