Courtesy: ISO 12402:2006 personal flotation devices
The rigid cork material eventually came to be supplanted by pouches containing watertight cells filled with kapok, a vegetable material. These soft cells were much more flexible and comfortable to wear compared with devices using hard cork pieces. Kapok buoyancy was used in many navies fighting in World War II. Foam eventually supplanted kapok for ‘inherently buoyant’ (vs. inflated and therefore not inherently buoyant) flotation.
The University of Victoria pioneered research and development of the UVic Thermo Float PFD, which provides superior protection from immersion hypothermia by incorporating a neoprene rubber “diaper” that seals the user’s upper thigh and groin region from contact with otherwise cold, flushing and debilitating water.
During World War II, research to improve the design of life jackets was also conducted in the UK by Edgar Pask OBE, the first Professor of Anaesthesia at Newcastle University. His research involved self-administered anaesthesia as a means of simulating unconsciousness in freezing sea-water. Pask’s work earned him the OBE and the description of “the bravest man in the RAF never to have flown an aeroplane”
The Mae West was a common nickname for the first inflatable life preserver, which was invented in 1928 by Peter Markus (1885–1974) (US Patent 1694714), with his subsequent improvements in 1930 and 1931. The nickname originated because someone wearing the inflated life preserver often appeared to be as large-breasted as the actress Mae West. It was popular during the Second World War with U.S. Army Air Forces and Royal Air Force servicemen, who were issued inflatable Mae Wests as part of their flight gear. Air crew members whose lives were saved by use of the Mae West (and other personal flotation devices) were eligible for membership in the Goldfish Club.
Devices designed and approved by authorities for use by civilians (recreational boaters, sailors, canoeists, kayakers) differ from those designed for use by passengers and crew of aircraft (helicopters, airplanes) and of commercial vessels (tugboats, passenger ferries, cargo ships). Devices used by government and military (e.g. water police, coast guard, navy, marines) generally have features not found on civilian or commercial models, for example compatibility with other items worn, like a survival vest, bulletproof vest/body armor, equipment harness, rappelling harness, or parachute harness, and the use of ballistic nylon cloth to protect pressurized CO2 canisters used for inflating the vest from injuring the wearer if struck by a round from a firearm. The ballistic cloth keeps the fragments from the canister from becoming shrapnel injurious to the user.