What must be done with facial hair before conducting a fit test for respirators?

Before conducting a fit test for respirators, it is essential to shave off facial hair. This requirement stems from the need for a proper seal between the respirator and the user's face. Any facial hair, including a beard, mustache, or even stubble, can create gaps that compromise the effectiveness of the respirator. If there is no secure fit, contaminants can enter the respirator, diminishing its protective qualities and putting the worker's health at risk.

While trimming hair or styling it differently might improve comfort, these actions do not guarantee the necessary tight seal that shaving achieves. Complete removal of facial hair is the only way to ensure that the respirator can adequately protect the wearer against hazardous substances. Thus, shaving is critical for safety and compliance with health regulations.