OC Oxygen reg on Insp.

[Pierre Farrugia]

Hello,

I am thinking of fitting an oxygen reg on the Oxygen side on my Insp. What you think about this? What reg. do you suggest,( pref. Scubapro )? Where do you attach this reg ?

[johnv]

I've never understood the point of an O/C reg permanantly attached to the O2 side of a rebreather with only a 2 or 3L cylinder. If the reg freeflows you are in the shit, think about the O2 pressure you surface from a deco dive with, now work out how long that gives you at 6m. Not long enough. if you really need O2 bailout take a stage.

surely you have enough clutter on your front with the air2, 2 handsets & 2 counterlungs, why add another 2nd stage for very little return. rather than add another reg, I'd ditch the air2, if you haven't already done so.

John

[DecoWarrior]

surely you have enough clutter on your front with the air2, 2 handsets & 2 counterlungs, why add another 2nd stage for very little return. rather than add another reg, I'd ditch the air2, if you haven't already done so.

Amen to that brother! agree 110 percent for how long its going to last you is it worth the hassle, if you need it that bad take another bottle!

[Wreckrat]

Personally i have fitted an O2 reg on my unit mainly because if the crap does hit the fan and bailout occurs then you are carrying a 3ltr of 100% that you cannot get at if you have to come off the loop.
Say a typical dive you use 40 bar out of 232, that leaves 192 (576 ltrs) take that with a breathing rate of 15ltrs/min @ 6m that equates to 24mins of breathing time, if the worst case scenario that bailout occurs at the end of the bottom time, and a deco obligation has been incurred however little, then i would have peace of mind that i could breathe pure O2 and get out of the water without the worry of DCI.
As for the clutter i have fitted an oceanic omega direct from the side of the O2 bar, over the right shoulder, and clipped neatly next to the O2 iinflator hose, i have a flow stop device fitted to prevent freeflow.
And i dont have to carry an extra tank if i'm doing dives no deeper than 40m with less than 20mins deco at 6m (aside from a 3ltr bailout strapped to the side of the unit)
My theory 'better some than none !'

[nigelH]

Originally Posted by Pierre Farrugia

I am thinking of fitting an oxygen reg on the Oxygen side on my Insp. What you think about this?

I have one. It has a TX40 with an Apex shutoff valve.

I fitted it because a 5m stop on O2 makes a lot of alpinest profiles look so much safer and today, doing BSAC's Practical Rescue Management Skill Development Course, it became our O2 kit on demand. You definitely need the shutoff valve as I have seen one freeflow and blow off enough gas to make them abort the dive.

[johnv]

Originally Posted by Wreckrat

Say a typical dive you use 40 bar out of 232, that leaves 192 (576 ltrs)

your numbers are fair enough if your starting O2 fill is 232 bar, which, I would suggest is not very typical. You are far more likely to start with less than 200, use more than 40 and have a higher SAC if your shiny CCR has gone tits up. Also, can you really breathe every last bar in your cylinder?

but each to their own.
John

[Wreckrat]

Agreed John, average fill 200ish and you should be able to breathe the tank inside out...almost, as you say each to their own, i would breathe as much as i could before heading for the sky blue, like i said better some than none.

[Decodiver]

I am with John and Decowarrior on this one.

I have never dived a CCR with OC regs on either the diluent or O2 side.

They are a recipe for losing all your gas and some OC numpty swimming up and trying to breath off your fluorescent "octopus".

No thanks.

[jknights]

Still seems like approx 500 litres is better than zero so I guess the answer is why not.

My Inspiration has a bailout regulator with a connector on it that allows me to unplug the gas (O2 or diluent) feed and plug the regulator into the feed. I have only just bought the unit and my Mod1 training starts next week so I don't know how it all works in real life -- but it all looks kinda cool to an OC steam train diver, hope the wings on the unit dont come off !!

[Doorduijn, Niels]

Pierre,

If you proceed with putting an OC reg on the Inspiration and assuming that your unit has Apeks for first stages, I would suggest that you use an Apeks TX-40 or higher. The T-series are somewhat smaller then the previous Apeks 2nd stages.

I would also suggest that you put a gas flow stopper on the reg. I once jumped in cold water and the diluent regulator (Apeks T40) of my unit went on free-flowing: 200 - 70 bar in no time. No fun, and also the reason why I personally would never put an O2 reg on the inspiration. The risk that you loose your inboard O2 may well be greater then the risk that you need to get of the loop. But as someone said before, each his own choice.

Rgs,

Niels Doorduijn
Holland