| Hi Les, I am using an mCCR (closed circuit) submatix. Not an SCR. I used nitrox 45 instead of air in the diluent bottle. The oxygen bottle had oxygen in it. It's not necessary but it gives an extra safety margin for shallow water diving. If you use air as a diluent and things go wrong with the O2 supply you can become hypoxic. It has happened with people using RB's in a pool.
Do you use an SCR Sub or a closed circuit Sub?
Cheers
Ian |