Stage switching

[And]

Originally Posted by graham_hk

Lastly, and furthermore, isn't it DIR procedure to go back to backgas on switchs? It is impossible not to have a CF with two stage regs around your neck ie using not the BG.

Hi

I agree with Graham, I think you would be switching to 10/70 BG for the break. The ideal is to switch to a gas which is the most 'normoxic' (ie .21 po2)at whichever depth you are at (remember some will do this at 9mtrs in a habitat) and that is best to help the lungs recover from the 100% exposure and extend the theoretical cns% measurement. I think it would be fraught with problems trying to switch between two stage bottles without tidying one up before you go to the next, so you go to backgas. .16 should not be a problem, if you are not working and calmly doing deco. Keeping your eyes on your teammates is key and/or having support divers there too, but I guess it depends on the circumstances.

I believe it was Steve Sherwood who died at WKPP in the early days, trying to get a stage bottle going and failing, as he had a number of stage regs hanging round his neck. It wasn't on deco, but that is one of the reasons why it is one stage at a time.

Andy