N95, KN95, and P100 Respirators (Respiratory Protection)

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N95, KN95, and P100 Respirators (Respiratory Protection)

The different resistance levels to oily aerosols and filter efficiency characterize respirators. Below are the various respirator classes:
  • N = not resistant to oil
  • R = resistant (somewhat) to oil
  • P = oil proof (strongly resistant to oil)
Efficiency ratings are based on the number of particles that can be stopped using the respirator. The efficiency ratings are:
  • 95% efficient at stopping particles 0.3 μm (microns) in diameter
  • 97% efficient at stopping particles 0.3 μm
  • 99.97% efficient (referred to as 100%) at stopping particles 0.3 μm in diameter
N95 and P100 respirators should meet NIOSH certification standards, whereas KN95s are manufactured and approved in China according to their standards. CDC, NIOSH, and the FDA (Food and Drug Administration) provide websites with information about approved masks and respirator devices according to the product manufacturer. The links to those websites are below: