<Tr> <Th> Related items </Th> <Td> Diving helmet, Diving regulator, Diver communications, Diving mask </Td> </Tr> <P> A full - face diving mask is a type of diving mask that seals the whole of the diver's face from the water and contains a mouthpiece, demand valve or constant flow gas supply that provides the diver with breathing gas . The full face mask has several functions: it lets the diver see clearly underwater, it provides the diver's face with some protection from cold and polluted water and from stings, such as from jellyfish or coral . It increases breathing security and provides a space for equipment that lets the diver communicate with the surface support team . </P> <P> Full face masks can be more secure than breathing from an independent mouthpiece; if the diver becomes unconscious or suffers an oxygen toxicity convulsion, the diver can continue to breathe from the mask . unlike a scuba mouthpiece which is normally gripped between the teeth . </P> <P> Full - face diving masks are often used in professional diving . They are relatively rarely used in recreational diving . </P>

Who made the first full face snorkel mask