At a glance
What matters most
- 01
N means the filter is not resistant to oil.
- 02
95 means at least 95% filtration in the NIOSH certification test.
- 03
A tight face seal is essential; facial hair can interfere with it.
- 04
N95 respirators do not remove gases, vapours or carbon monoxide.
What the N95 rating means
N95 is a U.S. NIOSH filter class. Approved products carry required markings including NIOSH, the filter class and a TC approval number that can be checked in the Certified Equipment List.
The rating describes laboratory filter performance, not a guarantee that every wearer receives the same protection.
Fit and use
- Choose an approved model and the correct size and style.
- Inspect it before use and discard it if damaged, dirty or damp.
- Put it on with clean, dry hands and perform a seal check every time.
- Use workplace fit testing and medical evaluation when required.
Important limitations
N95s filter particles; they do not supply oxygen or protect against gases and vapours. They are unsuitable for unknown, immediately dangerous or oxygen-deficient atmospheres.
Frequently asked questions
Does an N95 help with PM2.5?
A genuine, well-fitted N95 can reduce inhalation of airborne particles, including particles in the PM2.5 size range, but fit and correct use are critical.
Is N95 the same as a surgical mask?
No. An N95 is designed to seal to the face and meet a respirator standard; an ordinary surgical mask is not a tight-fitting respirator.
Can an N95 protect against carbon monoxide?
No. Carbon monoxide is a gas and is not removed by an N95 particle filter.
Primary sources
This reference was prepared from the following primary public-health and regulatory sources: