Ambient Pressure Diving

The scuba equipment manufacturer A.P.Valves or Ambient Pressure Diving is at Water-Ma-Trout in Helston in Cornwall in England. They make a variety of scuba gear including buoyancy compensator jackets and diving rebreathers.

The firm started in 1969 making a valve to attach to a stabiliser jacket buoyancy compensator to allow the diver to breathe from the stab jacket's inflation cylinder. They progressed to making divers' adjustable buoyancy life-jackets and stabiliser jackets, and then other sorts of diving gear.

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