Respirators, Fit Testing, OSHA Requirements
All respirators that rely on a mask-to-face seal need to be checked annually with either qualitative or quantitative methods to be sure that the mask fits properly to the wearer. The qualitative fit test procedures are based on subjective sensations of the respirator wearer, such as taste, irritation (inflammation), and smell, to a particular substance (test agent). The quantitative tests use measuring instruments to measure face-seal leakage. The specific workplace exposure level determines what constitutes an acceptable fit and which fit test procedure is required. For negative pressure air purifying respirators, users may rely on either a qualitative or a quantitative fit test procedure for exposure levels less than 10 times the occupational exposure limit. Exposure levels greater than 10 times the occupational exposure limit must utilize a quantitative fit test procedure for these respirators. Fit testing of tight-fitting atmosphere-supplying respirators and tight-fitting powered air-purifying respirators shall be accomplished by performing quantitative or qualitative fit testing in the negative pressure mode.