The federal government’s free N95 masks are now arriving in Minnesota pharmacies. Here’s what you need to know about the masks — another tool in fighting the COVID-19 pandemic.

What is an N95 mask?

Technically called “respirators,” these masks fit tightly to the face with the edges designed to form a seal around the nose and mouth. They usually have straps that stretch to the back of the head rather than loops over the ears. Respirators are certified by the National Institute of Occupational Safety and Health to filter out at least 95% of airborne particles.

Where can I get masks?

On Thursday, Jan. 27, masks were just beginning to trickle in across Minnesota. Posters at the Facebook page Minneapolis Vaccine Hunters were reporting limited success at Hy-Vee stores initially. Officials with CVS Health and Coborn’s said they expected supplies to start landing soon. Walgreens and Walmart are participating in the federal program nationally, but — as of Friday morning — the companies hadn’t provided details about any plans for Minnesota. Costco did not respond to questions from the Star Tribune.

Do I need to register beforehand or show ID?

No

Is there a limit on the number of masks I can have?

Up to three masks per person

Are there kid sizes available?

N95 masks are not designed for children, according to the Food and Drug Administration. “Although respirators may be available in smaller sizes,” the Centers for Disease Control and Prevention (CDC) said, “they are typically designed to be used by adults in workplaces, and therefore have not been tested for broad use in children.”

The Biden administration plans to soon start shipping high-quality masks for children, the Wall Street Journal reports. At an event earlier this year, a consumer group called Project N95 partnered with Hennepin County to distribute masks that aren’t N95s but are designed to give children more protection.

If a store runs out of masks, will they get more?

It’s unclear. Pharmacies in Minnesota on Thursday said they did not yet know the frequency of shipments from the federal government.

Can I re-use an N95 mask?

It depends on the mask’s condition. In health care settings before the pandemic, N95 masks were thrown away after one use. When COVID-19 hit and there was suddenly a shortage of personal protective equipment, hospitals started stretching supplies of their N95s, asking health care workers to re-use them on a rotating basis and store masks in paper bags between uses.

The federal government hasn’t provided much guidance on re-use, but Michael Osterholm, the director of the Center for Infectious Disease Research and Prevention at the University of Minnesota, said he re-uses his N95 masks for “days and days.” The masks are good, he said, so long as they don’t become soiled or damaged. For example, straps on N95 masks can break after repeated use.

The CDC advises: “Most publicly available respirators are disposable and should be discarded when they are dirty, damaged, or difficult to breathe through.”

Should I stop using cloth masks?

The CDC updated its guidance on masks in January to emphasize that some masks like N95s can provide more protection than others. At the same time, the agency acknowledged that some people don’t like the feel of N95 respirators and are therefore unlikely to use them consistently.

In the new guidance, the CDC said: “Some masks and respirators offer higher levels of protection than others, and some may be harder to tolerate or wear consistently than others. It is most important to wear a well-fitted mask or respirator correctly that is comfortable for you and that provides good protection.”

So, it depends?

Yes. Health care experts emphasize different aspects of the CDC’s message.

Dr. Priya Sampathkumar of Mayo Clinic agrees that N95s are much better in terms of filtration efficiency, but thinks many people won’t wear them. Back in 2020, Sampathkumar and other physicians supported people using cloth and surgical masks because they seemed to help slow transmission in hospitals.

Sampathkumar said in a recent interview: “I think that a flimsy cloth mask may not be good enough. A well-made cloth mask with several layers is good. A well-made surgical or medical mask is better. And an N95 is even better than that, but an N95 is almost impossible to wear for prolonged periods of time.

“So, if … you want to be ultra-cautious, you’re very vulnerable, and you want to make a quick trip to the drug store to pick up your prescription — an N95 might be OK if you have it, you’re comfortable wearing it and you want to do it. But to say that everyone must wear N95s or we give up and don’t do anything — I think that is the wrong path to go.”

Osterholm of the University of Minnesota has long championed N95 masks and other forms of higher-quality respiratory protection. Early in the pandemic, Osterholm raised questions about the evidence for wearing cloth masks, although he also offered qualified support for people wearing them.

In a recent interview, Osterholm said: “You achieve a substantial improvement in protection by wearing a tight-fitting N95 respirator. This is because, not only is it tight-fitting and doesn’t allow leakage around the side of the respirator, but in addition the special material it’s made from actually is a porous material, but it has an electrostatic charge in it.

“So, it still allows air to cross the material relatively easily compared to say a thicker cloth. But because of the electrostatic charge, it’s what makes it so effective in preventing the viruses from coming through. … I think this is a very major step forward as part of a layered approach – getting vaccinated, avoiding large crowds and wearing an N95 respirator can go a long ways in protecting you.”

What about KN95 masks?

KN95 masks are similar to N95s. Minnesota announced Thursday plans to distribute 2.1 million KN95 masks to community groups, local public health agencies, schools and other entities.

There are a few key differences, however. KN95s have ear loops rather than straps that go around the back of the head. Also, the masks are certified according to international standards while N95s meet U.S. standards.

A lot of people are fans of KN95s, saying they are more comfortable. The New York Times notes: “While you can find legitimate KN95 masks, the supply chain is riddled with counterfeits and there’s little regulation or oversight of the product. One study found that 60% of the supply of KN95s in the United States are counterfeit.”