The coveted nonsurgical N95 masks, which the Centers for Disease Control and Prevention says “offer the highest level of protection” against the novel coronavirus that causes COVID-19, are coming from the strategic national stockpile, a nationale cache of medical supplies.

Most of the pharmacies participating in the federal pharmacy vaccine program, including CVS CVS, +1.71%, Walgreens WBA, -2.41%, Walmart WMT, -1.02% and Sam’s Club, are also participating in the free N95 masks program. Customers are limited to three masks per person in what White House Coronavirus Response Coordinator Jeffrey Zients has called “the largest deployment of personal protective equipment in U.S. history.”

And the government is sending free at-home COVID-19 test kits to help slow the spread of the virus and stem the recent spike in hospitalizations and deaths amid the spread of the highly contagious omicron variant. While U.S. cases are starting to come down from recent peaks, hospitalizations remain above 156,000 a day, and deaths are still above 2,000 a day. 

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Below is what you need to know about picking up your free N95 masks. 

When and where are these free N95 masks available? 

Most of the retailers that joined the Federal Retail Pharmacy Program for COVID-19 Vaccination are also planning to join the distribution of the free N95 masks, including CVS, Walgreens, Kroger KR, -1.55%, Rite Aid RAD, -4.25%, Publix, Costco COST, +1.29%, Walmart and Sam’s Club. Some places, including Midwest grocer Meijer and supermarket chain Hy-Vee, have already reported receiving theirs in stores.

A Walgreens spokeswoman told the Washington Post and CNN that she expects some stores to begin offering the free masks this Friday, Jan. 28, and that the free face coverings will continue being issued on a rolling basis over the next few weeks. Participating stores will post signage to let shoppers know that the free N95 masks are available. 

CVS expects to receive the free masks and start handing them out in the coming weeks, a representative told CNN. 

As for health centers, a spokesperson for the National Association of Community Health Centers told CNN that the first 100 centers participating in the rollout will start distributing masks this week. The Health Resources and Services Administration expects the free masks will be made available to all health centers by mid-February. 

Indeed, all participating drugstores should also receive their supplies of N95 masks by the middle of next month, per the White House plan. 

How many N95 masks can I get? 

In order to give as many Americans access to these 400 million masks as possible, the free masks are limited to three per customer. So far, there haven’t been widespread reports of issues with people taking more than their allotted amount. 

Can N95 masks be used more than once?

Yes. While there is no hard and fast rule about exactly how many hours each mask can be worn, the CDC says that N95 masks can be used up to five times before they’re compromised. Keep in mind, however, that this guidance is for masks being used by healthcare professionals, who might wear those masks for an entire 8- or 12-hour shift. They’re not just slipping an N95 on to run to the supermarket, suggesting the average person can extend the life of a mask further.

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Experts generally recommend rotating through different masks during the week, and looking for signs that the mask no longer fits properly — such as stretched-out straps and overall mask looseness — or signs that the mask has become dirty. But the mask’s fit is key; that’s what ensures that your mouth and nose are best protected from inhaling virus particles. 

Where can I buy N95 masks after these free ones run out? 

There have been reports of N95 shortages and price gouging due to supply-chain issues and high demand for the more effective masks, which is one reason the government is providing free masks for potentially all Americans. But they can still also be found in stores and online. 

Unfortunately, counterfeit N95 and KN95 masks are rampant online. The National Institute of Occupational Safety and Health, or NIOSH, has a list of approved N95 respirators often sold at drugstores and home-improvement stores, and the CDC has this guide to identifying real vs. fake NIOSH-approved masks. And organizations such as Project N95, which works to protect communities by providing equal access to personal protective equipment like N95 masks and COVID-19 tests, are careful to source NIOSH-certified and FDA-cleared masks and testing kits. 

A box of 20 N95 masks is running about $40 to $50 on Project N95’s site, for example. Similarly, a 10-pack goes for around $20 at Home Depot and elsewhere.

What makes N95 masks so special? 

To be sure, wearing any mask is better than no face covering at all to help prevent spreading COVID-19. But public health experts have increasingly warned that the single-layer cloth masks that became popular early in the pandemic do not provide enough protection, particularly against the omicron variant. 

The CDC explains that the N95 respirators (commonly called “masks”) approved by the NIOSH filter at least 95% of airborne particles. The KN95 masks are similar, except they are certified differently; KN95 is the Chinese standard, while N95 is the U.S. standard. But KN95 manufacturers can seek emergency-use authorization from the Food and Drug Administration for use in healthcare settings. And the FDA has granted EUAs to several KN95 masks. 

The N95 and KN95 masks are made with an electrostatically charged material that actually catches smaller particles — preventing you from inhaling them — and filtering microscopic particles that are just a few nanometers in size. In comparison, cloth masks can be good at filtering large droplets, but smaller particles and aerosols potentially carrying airborne viruses can still pass through. 

Again, cloth masks are better than not wearing a mask at all, as multilayer cloth masks can still block 50% to 70% of fine droplets and particles, the CDC says, while N95s filter out 95% of particles. Check out this guide to how much more an N95 mask can protect you compared with a cloth or surgical mask.