An alternate method of getting air to the diver is the old garden hose trick. You still need a firest stage or some way of getting low pressure air into a hose that will take is. Drop the other end into the water and you can get breaths off it at depth.
In commercial diving it is referred to as breathing off your pnumo hose. The pnumo hose is a pnumophathometer that is usually attached vis a needle valve to a gage that reads in Feet Sae Water. Compressed air is plumbed to it off the breathing supply and shot down to the open end at the diver. When shut off the pressure of the water, at depth, is read on the gage topside to get the divers depth.
It is just an open ended hose and in commercial dive training you learn to berath off of it either by stuffing it into your helmet of just getting air straight out of it. Kind of like blowing air down a garden hose.
In commercial diving it is referred to as breathing off your pnumo hose. The pnumo hose is a pnumophathometer that is usually attached vis a needle valve to a gage that reads in Feet Sae Water. Compressed air is plumbed to it off the breathing supply and shot down to the open end at the diver. When shut off the pressure of the water, at depth, is read on the gage topside to get the divers depth.
It is just an open ended hose and in commercial dive training you learn to berath off of it either by stuffing it into your helmet of just getting air straight out of it. Kind of like blowing air down a garden hose.