The Biden administration will give out 400 million free N95 masks next week. So how effective are they at protecting people from COVID-19?

The CDC recently changed its guidance to recommend that anyone who can wear the more protective N95 and KN95 masks should do so. The Inquirer spoke to Martin Blaser, director of Rutgers University’s Center of Advanced Biotechnology and Medicine, to get some insight on the level of protection N95 masks offer.

Which are better: cloth masks or N95 masks?

The masks available to protect people from COVID-19 infection can be broken down into three levels, Blaser said.

There are the cloth masks, which are the least protective, owing to their larger pores and some offering only one layer of material for protection from particles of COVID-19. Then there are the readily available surgical masks, which are two-ply and reasonably protective, as they have two layers of protection.

But the gold standard of protection is the N95 mask, he said.

(KN95 and KF94 masks can be used interchangeably with N95s and are designed to filter out a minimum of 94% of particles. The masks only differ in country of origin and design differences, like ear loops vs. straps.)

“It’s all about the size of the pores in the mask,” Blaser said. “A mask is like a sieve. A sieve has pores. The N95 has very small pores. They retain 95% of droplets that come their way. That’s where the name N95 comes from.”

The fibers in N95 masks are pressed closer together than in cloth masks and have an electrostatic charge that makes molecules stick to the mask instead of passing through.

“The virus is spread in very small droplets,” he said. “So the mask is a barrier. If somebody coughs out a million virus particles, maybe a thousand of them are going to reach you. And maybe if you have a mask on, none of them are going to reach you.”

Are cloth masks better than no mask?

Ultimately, if a person does not have access to or is uncomfortable wearing an N95 mask, a cloth mask is better than nothing, Blaser said.

The average person outside of a health-care setting doesn’t really need an N95 mask, he said, with a surgical mask being sufficient for daily protection.

“Surgical masks, I think these are the great utility players,” he said. “These are masks that would really be helpful if people used all the time because they’re comfortable and they’re not that expensive. They’re highly available. People can wear them for long periods of time. And people can reuse them.”

Though cloth masks are limited in protection, they are more available than N95 masks. For Blaser, the key is for as many people as possible to don some sort of mask.

“But my view is that any mask is better than no mask,” he said.

CDC guidance has changed on N95 masks. Can we still go by its guidance?

Since the beginning of the pandemic, the CDC’s guidance on whether to wear masks or not and which types to wear has fluctuated.

Early in the pandemic, the CDC said N95 masks should be reserved primarily for frontline health-care workers. The shift to recommending that the average person should use N95 masks if possible came Saturday, nearly two years into the pandemic.

For Blaser, the guidance is merely evolving alongside the pandemic.

“I think people have been too critical of the CDC,” Blaser said. “We have an ongoing epidemic. And the epidemic keeps changing, as we’ve all seen. And so the advice has to keep changing, too.”

What’s most important when choosing a mask?

Wearing masks — any type one can wear — is crucial to changing the tide of the pandemic, Blaser said.

Along with vaccination and social distancing, masks are vital weapons in the fight against COVID-19 and its continued spread, he said. For that reason, Blaser recommended that people choose the mask that’s most protective while still being comfortable enough to wear daily.

“The principle is that masks save lives,” he said. “Masks protect people. People should use the best mask that they can that they’re comfortable with that they will wear. If you have an N95 and it’s uncomfortable and you don’t wear it, it’s not helping you very much.”