Performance and acceptance of respirator facial seals.

Three respirator full face masks with different paripheral seal designs (flat, inner flap, and pneumatic) were modified to permit study of the facial seal component. Twelve subjects participated in the study. Each subject completed a three-hour test session on each mask. The first half of each session was devoted to a study of leakage at five seating forces; the second half of the session was devoted to a comfort study of the same mask under the same five seating forces. To test for the differences in' leakage for a given seating force a uranine aerosol test was used to challenge the integrity of the facial seal and permit quantitative measurement of percent leakage. Differences in apparent seating force (and therefore comfort) between the three facial seal designs were studied utilizing a psycho-physical technique. A suggested physiological correlate of comfort, galvanic skin potential, was also measured during the second half of the session. Significant differences were noted in the performance of one o...