The arrival of the highly contagious omicron variant has spurred a shift in face mask advice. Many experts are telling Americans that instead of wearing just any mask, they should be upgrading to the best one they can get their hands on. That, as it turns out, is a respirator mask, also known as an N95.
On Jan. 14, the Centers for Disease Control and Prevention (CDC) updated its guidance to acknowledge that these masks provide the highest level of protection against the virus that causes COVID-19, and that certain people, including older adults and individuals with underlying health conditions, may want to consider wearing one now that they are no longer being reserved for health care workers. (The CDC stops short of officially recommending the high-efficiency masks over others, instead maintaining that any mask is better than no mask.)
There are a few things to know about N95s before switching to one, including how many times you can reuse the mask. Here’s what the experts have to say.
How effective are N95s?
Just as the name suggests, N95 masks that have been approved by the National Institute for Occupational Safety and Health (NIOSH) — here’s how to tell if yours is NIOSH-approved — are at least 95 percent effective at filtering out virus-sized particles, including the virus that causes COVID-19, when worn correctly. This means the mask should fit snugly over your nose and mouth, forming a tight seal, without any gaps along the edges or around the nose.
“If you're in a crowded place where there are people who maybe have COVID, wearing an N95 mask means you're cleaning the air much better right before you breathe it in,” says M. Patricia Fabian, an associate professor in the Department of Environmental Health at the Boston University School of Public Health. What’s more, N95s help to block droplets and particles that you breathe out (or cough or sneeze out) from reaching others.
KF94 and KN95 masks also fall into the category of respirators. The difference is they are designed and tested to meet international standards. The CDC says KN95s offer slightly less protection than NIOSH-approved N95s but are still more protective than cloth masks.
In addition to older adults and people at higher risk for complications from a coronavirus infection, the CDC says people who are caring for someone who is sick with COVID-19 should consider wearing a respirator mask. So should individuals who interact with the public daily, like grocery store workers and bus drivers. Taking public transportation or hopping on a cross-country flight? That’s also a good time to wear an N95 or something similar.
How many times can you wear an N95?
Unlike cloth masks that can be washed and reused, N95s do not have as long of a lifecycle. For starters, they are not washable. One of the layers in the mask is electrostatic; it’s meant to attract and trap particles in the air that's breathed in, Fabian explains. Wash it with soap and water and “you’d ruin at least one of the layers, if not more,” she says.
In fact, the CDC says respirator masks should be tossed in the trash if they get wet or dirty. If your mask stays clean, consider it good for about a week, says Aubree Gordon, associate professor of epidemiology at the University of Michigan School of Public Health. (This advice is for the general public only; health care workers abide by different rules.) However, if you’re only wearing your N95 for short bursts — say, to the grocery store or to run a few errands — you can likely reuse it for longer, Fabian points out.
The key is to pay attention to the “structural integrity” of the mask, says Megan Conroy, M.D., a pulmonologist at The Ohio State University Wexner Medical Center. For example, if the straps get too stretched or the seal around your face is no longer snug, it’s time for a new one.
Also, if you notice that it becomes more difficult to breathe in the mask, it’s time to retire it. “It's a filter, so if that filter starts to get clogged up, it's going to get harder to breathe in,” Gordon says. “If it's not feeling as comfortable anymore, or if it's looking bad or not fitting well, that would be the time” to stop wearing it.
Is there a way to prolong its use?
Definitely. Tossing a respirator mask in a purse or backpack with your phone, keys, wallet and other on-the-go essentials isn’t a good idea. Storing it in a paper bag between each use, however, is.
This will “help keep it clean and protected” in a breathable environment, Gordon says. The CDC also recommends storing masks that are not wet or dirty in paper bags between each use. Avoid storing your mask in an airtight container, Gordon adds.
If you have access to more than one N95, rotate between each. When you’re done with one, take it off and put it in a paper bag marked with the day of the week or whatever organizational system you prefer, Gordon says, and wear another N95 in the meantime. “Wait until you are past the mask’s quarantine period or disinfecting period” before wearing it again, she says. In experimental studies, which may differ from real-world conditions, the coronavirus can stay alive on surfaces for up to 72 hours, according to the CDC.