In the 50's and 60's there were no BC's. Divers used inflatable Mae West (horse-collar) style life jackets that were designed for airplane passengers. These life jackets were strictly for emergency use at the surface and were inflated by a small CO2 cartridge.
In the 70's Buoyancy Control Devices were being developed for use by divers. Most were adaptations of the front mounted horse-collar life jackets. They were made a little larger, equipped with an over-pressure valve and a corrugated hose with a mouthpiece for inflation. Some had automatic inflators so the diver could inflate them without taking his regulator out of his mouth.
Jacket style and back mounted BC's also started to show up. Competition developed between the manufacturers of the differing designs. Makers of the front-mounted BC's claimed that other designs would not turn an unconscious diver face-up and were therefore unsafe. This argument resonated with many instructors who were used to the older front-mounted safety vests.
My instructor, in 1973, did not trust any BC's and taught against them. He did not think a good diver should have to rely on such a "crutch." He later relented but never would accept anything other than a front-mounted, horse collar style.
In the 70's Buoyancy Control Devices were being developed for use by divers. Most were adaptations of the front mounted horse-collar life jackets. They were made a little larger, equipped with an over-pressure valve and a corrugated hose with a mouthpiece for inflation. Some had automatic inflators so the diver could inflate them without taking his regulator out of his mouth.
Jacket style and back mounted BC's also started to show up. Competition developed between the manufacturers of the differing designs. Makers of the front-mounted BC's claimed that other designs would not turn an unconscious diver face-up and were therefore unsafe. This argument resonated with many instructors who were used to the older front-mounted safety vests.
My instructor, in 1973, did not trust any BC's and taught against them. He did not think a good diver should have to rely on such a "crutch." He later relented but never would accept anything other than a front-mounted, horse collar style.