Well, I got some great responses. Is it a good idea? Maybe not but it sure got me thinking. It's less about wanting to do it than it is about whether it can be done. I do believe that vaping rather than smoking will be a great benefit to me as a diver. I will suck far less air at depth with healthy lungs. I think rigging a small spare air canister is the only viable option. The PV would have to be in a hose between the canister and the mouth piece. The just grab a hit off the canister every once in a while. This was just a lark, but a good puzzle for me. One poster mentioned the pressure being a problem and that could be a difficult one. I just don't know what effect that would have on the battery, atomizer or the vapor itself. The deeper you are, the more compressed the air is so you go thru your tank alot faster. You might get a hell of a hit off the PV! Testing is in order. I will be diving in Mexico on the 18th. I'll try the spare air can rig then, if I can rig it. If I do it my dive buddy will have to get a picture of the vape bubble I let out! If it happens, It will be posted here. I've tried far stranger things!