diving helmet

Diving helmets are worn by mainly by professional divers engaged in surface supplied diving.The helmet seals the whole of the diver's face from the water, allows the diver to see, provides the diver with breathing gas, provides an anchor point on the diver for the umbilical supplying the breathing gas, protects the diver's head when doing heavy or dangerous work, and provides voice communications with the surface. If the diver becomes unconscious, the helmet is more secure than breathing from a mouthpiece, which must be gripped between the teeth.
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