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Safety training        Rebreather apparatus
The rebreather apparatus (or airpocket) is a plastic bag with a tube, mouthpies and valve. This would give the passenger more time to escape from underwater.

Just before they submerge, the person breathes out into the bag. They will then rebreath this air for the next minute or so. They can do this because exhaled air still contains about 80% of the original oxygen.