A pressure helmet (from the abbreviation "hermetic helmet") is a part of the protective clothing (personal protective equipment, equipment) of a pilot or astronaut, which is part of a high-altitude compensating suit and high-altitude spacesuit. An airtight helmet of a special design that gives the pilot (cosmonaut) the opportunity to fly at high altitudes (suborbital and orbital) when the cabin of the aircraft is depressurized and ensures his survival in these conditions and during ejection. The helmet is equipped with a viewing glass with a light filter that protects the eyes and face of the pilot or astronaut from the effects of thermal and ultraviolet rays of the Sun. Phones and radio microphones are placed inside the helmet.
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