Field qualitative fit tests were conducted at 10 separate companies in the Northwest of England to determine the proportion of leaking respirators in a cross-section of pharmaceutical manufacturing industries. The 3 M FT-10 Qualitative Fit Test Apparatus was used to test a total of 211 half-face particulate respirator wearers, Participants wore their own respirators and were asked to don them as they would normally. In all cases, no specific intervention had occurred prior to testing. Results indicated a failure rate of 69% (of the 211 subjects tested, 145 respirators were leaking), Successful results were not associated with the frequency of use (p = 0.71) or years of experience wearing respirators (p = 0.59). Similarly, successful results were not associated with respirator training in the current job (p = 0.38) or training in previous jobs (p = 0.49). Leakage was not consistent across the 10 companies, with two companies exhibiting a 100% failure rate while another company had 26 successful tests in 50 wearers (52% pass rate). Only 35 of the 211 participants performed a negative pressure test. Of these, 80% successfully passed the test, which was significantly greater than the 22% pass rate among those who had not performed the pressure test (p < 0.001). (C) 1999 British Occupational Hygiene Society. Published by Elsevier Science Ltd, All rights reserved.
