Special Physiologic Problems in Submarines
Escape from Submarines. Essentially the same problemsencountered in deep-sea diving are often met in relation to submarines, especially when it is necessary to escape from a submerged submarine. Escape is possible from as deep as 300 feet without using any apparatus. However, proper use of rebreathing devices, especially when using helium, theoretically can allow escape from as deep as 600 feet or perhaps more.
One of the major problems of escape is prevention of air embolism. As the person ascends, the gases in the lungs expand and sometimes rupture a pulmonary blood vessel, forcing the gases to enter the vessel and cause air embolism of the circulation. Therefore, as the person ascends, he or she must make a special effort to exhale continually.
Health Problems in the Submarine Internal Environment.
Except for escape, submarine medicine generally centers around several engineering problems to keep hazards out of the internal environment. First, in atomic submarines, there exists the problem of ra-diation hazards, but with appropriate shielding, the amount of radiation received by the crew submerged beneath the sea has been less than normal radiation received above the surface of the sea from cosmic rays.
Second, poisonous gases on occasion escape into the atmosphere of the submarine and must be controlled rapidly. For instance, during several weeks’ submer-gence, cigarette smoking by the crew can liberate enough carbon monoxide, if not removed rapidly, to cause carbon monoxide poisoning. And, on occa-sion, even freon gas has been found to diffuse out of refrigeration systems in sufficient quantity to cause toxicity.