Full-face diving mask facts for kids

Quick facts for kids
Full face diving mask

The AGA Divator full face mask is used by military and civilian divers
Other names	Band-mask
Uses	Provision of breathing gas, underwater vision, and sometimes communications for underwater divers
Inventor	Yves le Prieur
Related items	Diving helmet, Diving regulator, Diver communications, Diving mask

A diver in a pool wearing an AGA full face mask

A diver wearing an Ocean Reef full face mask

Head protection helmet for use with Ocean Reef 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, 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.

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.

Full-face diving masks are often used in professional diving. They are relatively rarely used in recreational diving.

Safety

It may take a fairly long time to remove the mask to switch to breathing from the atmosphere. To avoid this, some full-face masks have a valve to switch between breathing from the set and breathing from atmosphere. The 'dive/surface valve', or 'snorkel valve', should be easily operated by the diver, even if wearing thick diving gloves, but not projecting so far that it can be easily knocked against things in low visibility water or in the dark, or in hand-to-hand combat underwater.

A full-face mask provides better security of breathing gas supply than a half-mask if there is a risk of the diver losing consciousness underwater.

The mask faceplate is generally a high impact strength polymer which is securely attached to the skirt or frame. A failure of the faceplate can be a life-threatening incident with some full face masks, as the water will flood into the oro-nasal inner mask and compromise the air supply. This problem is avoided by the masks which include a mouthpiece.

Not all divers will get a satisfactory seal from the skirt of any given full-face mask, as face shapes and sizes differ, but most divers will be able to find a mask that works for them. A major flood caused by a temporarily dislodged mask is easily drained by purging after replacing it in the correct position, and adjusting the straps if necessary. Lesser leaks will usually drain automatically from the mask through the exhaust valve of the demand valve or a purge valve fitted for that purpose as long as the mask is orientated with the valve at the low point. If there is too much water in the mask to allow inhalation it can usually be cleared using the purge button on the demand valve.

History

A full face diving mask was invented by Yves le Prieur in 1933.

The free-flow type of full-face mask is also sometimes referred to as a Jack Browne rig, named for a DESCO engineer who designed an early version of a full-face mask with a surface-supplied free-flow air supply.

See also