What does the 'N' indicate in an N-95 type of respirator?

What does the 'N' indicate in an N-95 type of respirator?

• A. Negative pressure
• B. Not resistant to oil
• C. Negative fit
• D. Not reusable

Answer: (B)

The letter N refers to oil resistance. In the NIOSH labeling system for filtering respirators, N means Not resistant to oil, while R means oil resistant and P means oil proof. This matters because oil aerosols can degrade or clog filters that aren’t oil resistant, reducing performance in oily environments. The 95 portion of N-95 indicates that the respirator filters at least 95% of non-oil particles under standard testing, but that doesn’t address fit or reuse. Fit is determined by how well the user seals the respirator to the face, and reuse depends on the device design and decontamination methods. So the best description is that the N indicates not resistant to oil.

The letter N refers to oil resistance. In the NIOSH labeling system for filtering respirators, N means Not resistant to oil, while R means oil resistant and P means oil proof. This matters because oil aerosols can degrade or clog filters that aren’t oil resistant, reducing performance in oily environments. The 95 portion of N-95 indicates that the respirator filters at least 95% of non-oil particles under standard testing, but that doesn’t address fit or reuse. Fit is determined by how well the user seals the respirator to the face, and reuse depends on the device design and decontamination methods. So the best description is that the N indicates not resistant to oil.