Full face diving mask

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 or demand valve 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, it increases breathing security and provides a space for equipment that lets the diver communicate with the surface support team.

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 mouthpiece which must be always gripped between the teeth.

Full-face diving masks are often used in professional diving. They are relatively rarely used in recreational diving, where they protect the face from cold water or stings, such as from jellyfish or coral, and prevent the discomfort derived from gripping a mouthpiece between the teeth for long periods.