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The main purpose of these lifesaving masks is to prevent wearers from dying in poisonous atmospheres, although a breathing mask can be used in several other circumstances. For example, in conjunction with other protective gear the breathing mask provides precious air to those operating in the vacuum of space. They can also be used while diving underwater for long periods of time without the use of a submersible. Spaceships or stations have also been known to store these masks for their crews in case they are damaged and begin leaking their atmospheric gasses into space.
Many factions and security agencies attach these breathing masks into body armors as an inner component of helmets, like those used by Stormtroopers and Mandalorian soldiers. Varying from model to model, filters on these units are usually expended after anywhere from one to six hours, depending on the toxicity of the contaminants in the local air. However, when the air canister is emptied, inexpensive replacement filters can be snapped into place in seconds. Without other equipment a breathing mask provides no protection against a vacuum and does not shield users from corrosive atmospheres. In addition, these devices only work for short periods of time, as both their air supplies and filters are eventually depleted.