RPE Fit Testing Training Course
Quantitative Controlled Negative Pressure (CNP) Method (Quantifit2)
CNP is a method that has been established in the US for many years, but is relatively new to the UK.
It works by creating and maintaining a negative pressure in the wearer’s mask and then measuring the leakage of air into the mask during an 8 second test period.
This method can be used to fit test half-masks and full-face masks.
Under the HSE protocol (INDG 479) there are different challenge pressures for half-masks and full-face masks.
An equivalent fit factor can be produced, so the result can be compared to HSE’s stipulated minimum fit factors.
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Dust2noise is the only organisation in the UK to have a CNP RPE fit testing course – Fit2Fit Approved. The course is delivered by a Fit2fit Accredited CNP Fit Tester and Chartered Occupational Hygienist.
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