Does your mask fit? Is the mask leaking? Face fit testing of Respiratory Protective Equipment (RPE) is a legal requirement. RPE must be face fit tested as part of the selection process through either a quantitative or qualitative means. Quantitative uses a portacount, the fastest way to reliably fit test any tight-fitting respirator. This method eliminates the guesswork associated with the qualitative method by calculating the results and automatically printing your certificate.