Will an N-95 mask protect the wearer against the virus that causes COVID-19?

The short answer, according to OSHA, is yes.

“When an infected person expels the virus into the air by activities like talking, coughing, or sneezing, the airborne particles are composed of more than just the virus,” OSHA wrote in a recently published list of frequently asked questions about the coronavirus.

OSHA explained that the virus is part of larger particles that are made up of water and other materials such as mucus.

“These larger particles are easily trapped and filtered out by N95 respirators because they are too big to pass through the filter,” OSHA said. “This is called mechanical filtration.”

Mechanical filtration is just one way that respirator filters keep particles from passing through the filter.

“An electrostatic charge also attracts particles to fibers in the filter, where the particles become stuck. In addition, the smallest particles constantly move around—called 'Brownian motion'—and are very likely to hit a filter fiber and stick to it,” the agency explained.

OSHA published the FAQs because it said it’s aware of false claims stating that the N95 respirator filter does not capture particles as tiny as the virus that causes COVID-19.

In fact, the new FAQ explains why an N95 respirator is effective at protecting users from the virus.

OSHA understands there is a shortage of personal protective equipment and, in response, has temporarily adjusted its respiratory protection standard.

The agency previously issued several memos to its safety and health compliance officers, allowing them to exercise enforcement discretion when considering whether to issue citations under the respiratory protection standard and similar provisions of other health standards.


For more information, contact CBIA’s Philip Montgomery (860.244.1982).