A record of experiments carried out by the Royal Naval Personnel Research Committee and the Department of Experimental Medicine, Cambridge, during 1950-51 (opening intertitle). To guard against exposure, experiments are carried out in the Arctic, Britain and the tropics on a self erecting inflatable raft. An inflatable exposure suit is also tested. The first experiments of the inflatable raft took place at Tromsø Fjord, Norway in February 1950 over five days. There is time for recreation skiing. In Harwich, different styles of 'tent' are tried with a mass exodus from the quayside. In Cambridge, the tent self-erects at a college swimming pool. The men clamber in. Boarding proves to be difficult for one untrained man wearing a life jacket. A rope scrambling net is added; followed by an armhold; followed by a ladder. A single man proves that he can right the capsized dingy. Singapore 1950, the experiments on the dinghies continue in the tropics. The men are mustered so that they can be examined briefly in turn (they are all in good health). Rosyth 1951, despite cold external temperatures, the interior of the tents become very hot; the temperature is recorded via a series of equipment. North Sea 1951, the evacuation of a ship onto life rafts takes place. Further modifications are made to the latest raft in 1953. Experiments to address seasickness are abandoned due to exceptionally heavy seas. They resume later in a swimming pool with a wave making machine with volunteers.