Skretvedt O T, Loschiavo J G
Am Ind Hyg Assoc J. 1984 Jan;45(1):63-6. doi: 10.1080/15298668491399389.
The effect of facial hair on the face seal of negative-pressure respirators, both half-masks and full facepieces, has been investigated. Three hundred and seventy (370) male employees were fit tested both qualitatively and quantitatively. Of these, sixty-seven (67) had fully established beards varying in length, shape, density and texture. Bearded subjects consistently failed the qualitative fit test protocol. Quantitative fit testing with half-mask respirators indicated that bearded employees had a median fit factor of 12 (8% leakage). A median fit factor of 2950 (0.03% leakage) was obtained on clean-shaven employees. An average two hundred and forty-six (246) fold drop in protection was experienced by bearded employees. With full facepiece respirators, the bearded employees had a median fit factor of 30 (3% leakage). A median fit factor of greater than 10 000 (less than 0.01% leakage) was obtained on clean-shaven employees. At least a three hundred and thirty (330) fold drop in protection was experienced by bearded employees. Results indicate that the presence of a beard greatly increases the leakage through the respirator face seal, and this leakage should not be permitted when employees are required to wear respirators.
人们已经对胡须对面部毛发对负压呼吸器（包括半面罩和全面罩）面部密封的影响进行了研究。对370名男性员工进行了定性和定量的适合性测试。其中，67人蓄有长度、形状、密度和质地各异的完全成熟的胡须。蓄须者始终未能通过定性适合性测试方案。对半面罩呼吸器进行的定量适合性测试表明，蓄须员工的适合因数中位数为12（泄漏率8%）。剃须员工的适合因数中位数为2950（泄漏率0.03%）。蓄须员工的防护能力平均下降了246倍。对于全面罩呼吸器，蓄须员工的适合因数中位数为30（泄漏率3%）。剃须员工的适合因数中位数大于10000（泄漏率小于0.01%）。蓄须员工的防护能力至少下降了330倍。结果表明，胡须的存在会大大增加通过呼吸器面部密封处的泄漏，而当要求员工佩戴呼吸器时，这种泄漏是不允许的。
