- Orinasal mask
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An orinasal mask is a breathing mask that covers the mouth and the nose only. It may occur independently, as an oxygen mask, or on some anaesthetic apparatuses, or it may occur inside a fullface mask on a scuba set or an industrial breathing set to reduce the amount of dead space. According to how it is designed for use its lower edge may seal on the front of the lower jaw or may go under the chin.
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