The APF of RPE for asbestos work should never be below 20. According to the HSE, the RPE should have an APF that’s higher than the calculated necessary value. This is the best way to ensure the most protection possible.
Respirators filter out hazardous substances so the worker only breathes in clean, safe air. However, RPE only works if it fits the wearer correctly. Face-fit testing is used to determine whether or not RPE fits the person wearing it.
During face-fit testing, professional testers, asbestos workers, or both determine if particles are getting inside the mask. If particles are found to be leaking into the mask, that means the equipment isn’t sealing properly.
Testing methods range from using particles with an odour so the wearer can smell if they’ve leaked in to using high-tech equipment that counts the particles in the respirator. Also, the wearer will be asked to move around the same way they’re expected to on the job site for a real-world experience.