What does qualitative respirator fit testing primarily check for?

Qualitative respirator fit testing primarily checks for the detection of irritants to determine if there is an adequate seal between the respirator and the wearer's face. This type of fit testing uses a test agent, usually a harmless irritant like a bitter or sweet substance, to evaluate whether the wearer can detect the agent while wearing the respirator. If the individual can taste or smell the agent, it indicates that the mask does not fit properly and may not provide the intended protection from airborne contaminants.

The focus on irritant detection is crucial because it directly relates to the respirator's effectiveness in preventing exposure to harmful substances, particularly in environments where lead or other hazardous materials may be present. Proper fit is a key factor in ensuring safety during lead abatement and similar operations.