| 摘要 |
<p>A respirator comprising a respirator facepiece (1), a first sealing means (7 ) suitable for forming a seal on the face of a user so as to define a first cavity between the first sealing means, the respirator facepiece and an area of the use~s face comprising the eyes, mouth and nose, a second sealing mean s (6) suitable for forming a seal on the face of the user so as to define a second cavity, the second cavity being formed between the second sealing mea ns (6), the first sealing means, a portion of the face of the user and optional ly the respirator facepiece (1), a respirator air inlet (4) for conducting inhaling air to the first cavity, a respirator air outlet (3) for conducting exhaled air from the first cavity, and an air pressure supply means suitable for supplying pressurised air to the second cavity whereby in normal operati on air is inhaled and exhaled solely through the first cavity and so substantially no air pressure differential exists between the ambient atmosphere and the second cavity which will allow ambient air to enter the second cavity.</p> |
