BREATHING EQUIPMENT FOR AIRCREW

摘要

A facemask incorporating breathing equipment for use with a flying helmet (2) comprises a rigid outer shell (4) in which a flexible face-piece (3) is housed whose periphery makes an airtight seal with the pilot's face (1). The face-piece (3) includes an inhalatory valve (11) and an expiratory valve (9) and the rigid shell (4) is attached to the helmet (2) by a harness (5) which keeps the shell (4) at a fixed distance from the helmet (2). Inflatable means (15, 20) are provided between the shell (4) which are inflated to press the periphery (14) of the face-piece towards the pilot's face when the pressure of breathable gas supplied to the interior of the mask and to said inflatable means increases above that required for normal breathing. Alternatively, the face-piece (3) can include extendable means in the form of a re-entrant section (30, 34, 35) or bellows section (36) which extends in a direction towards the pilot's face when the pressure of the breathable gas supplied to the interior of the face-piece (3) increases above that required for normal breathing.