---
title: OHD | The Benefits of Switching to CNP
description: The benefits of switching to Controlled Negative Pressure technology for mask fit testing. Fit testing with ambien aerosol. Quantitative Fit Testing. Qualitative Fit Testing. Mask Fit Testing.
---

# WHAT IS THE CNP METHOD FOR MASK FIT-TESTING?

OHD created a device that uses air as the test agent, the Quantifit. Our patented Controlled Negative Pressure (CNP) technology generates a challenge pressure that is equivalent to the harshest of environments. To get a better understanding of our OSHA, NFPA and ISO-approved method of fit-testing, check out the video above!

 

Need to talk to one of our Fit Test Specialists? Shoot us your info below and we will get right back with you!

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