Justin Lobdell - Oct 2, 2019

OSHA Approves New Fit Test Protocols

This past week, OSHA approved two new fit testing protocols: the modified ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol for full-facepiece and half-mask elastomeric respirators, and the modified ambient aerosol CNC quantitative fit testing protocol for filtering facepiece respirators. Both protocols are variations of the original ambient aerosol CNC protocol, but have fewer test exercises and shorter exercise duration.

OHD and patented controlled negative pressure (CNP) technology are the pioneers of faster fit testing. This was exhibited by the Redon protocol, released in 2004. The newly approved OSHA protocols for CNC technology allow CNC methods to rival CNP’s speed, but OHD is proud to say that the best respirator fit test is STILL the fastest. The new modified CNC methods clock in at 2 minutes and 29 seconds. CNP’s Redon protocol can be performed even quicker, clocking in at under 2 minutes.

No matter how fast CNC becomes, it will never be able to compare to CNP technology. The Quantifit(R) uses air molecules with an ambient concentration around 2 x 1024 molecules/mL of air and relies on sonic wave propagation which occurs at sonic velocity. Simply put, when the Quantifit(R) creates a controlled negative pressure that mimics the inhale of an average human working at a moderate rate, it is creating an environment that will have air fighting to get into the mask in any way possible.

No one is ever opposed to faster fit testing, but with CNC, you’re leaving a lot up to chance. The chance you have enough particles, the chance a particle is the right size range, the chance the probe will pick that particle up instead of your nose or mouth, the chance that this indirect measurement will be enough to know that your mask is protecting you. Does taking this chance more quickly improve its chance of protecting you?

When it really counts, how would you want your mask fit tested? Take the challenge today. Test your mask. Test with confidence.

Take The Fit Test Comparison Challenge!


Written by Justin Lobdell