Quote: (Originally Posted by
Drmike)
Has anyone much experience using O2 for suit inflation?
Yes. Been using 100% Industrial Grade O2 in my suit, and occasionally wing, on almost every dive since I got my Inspo. Sometimes I've just used rich nitrox's when using my deco bailout.
On the skin bend issue: From the informal discussions with people who know about these things, I have not found any theoretical issues. I suspect there is a thermal advantage and intuitively think it's better from an ICD perspective, although I have no evidence for this.
What I don't do: I don't usually carry anything electrical (car remote lock) etc, and never flammable (charcoal handwarmers, lighter) inside my DS. If I was to take my GPS/mobile down with me, it would probably go in an Aquapac. I'm not religious about this, I just don't usually take stuff inside my suit. If I do, it's damp in there so I put them in something.
Advantages:
O2 is relatively cheap for me so it saves me using a third cylinder for shallow dives. It allows extra redundant buoyancy - I've switched the Inspo O2 inflator hose onto my DS mid-dive before now when my inflation/lift bag cylinder ran out. That still left the dil to use. If you use O2 in your inflation cylinder, you now have redundant O2, and running out of O2 is worse than a loop flood in my book.
Disadvantages:
Scares people.
My feeling is that inside my DS is a dark, damp, well-earthed environment. There is no obvious source of ignition there. There isn't a great deal of O2/gas in the suit and should the worst happen, I will flood the DS via the neck seal (and disconnect the DS feed). I then have extra buoyancy in my autoblob and gas blob to back up my wing in compensating for the loss of buoyancy if a fire has burnt through the suit.
You can see from the length of time I've been doing this that I don't consider DS O2 fires likely.
I've heard of only one incident using rich nitrox in a DS. The Darwin Candidate decided that a burning charcoal handwarmer was appropriate in a high O2 environment inside his suit...
