How much can medical masks take?
Where do you typically keep your high-quality medical-style masks?
A. In several brown paper bags marked with the days of the week, lined up on the window sill.
B. Hanging on hooks near the door. C. Tucked in a plastic bag in my purse or backpack.
D. Sometimes I find one stuffed in my pocket or on the floor of my car.
If you answered “D,” don’t be embarrassed. I live with mask chaos at my house, too. Masks are everywhere — on hooks and doorknobs, in drawers, stuffed in coat pockets and backpacks. And yes, I have grabbed a mask from the floor of my car. (Please don’t do this. A study by Clorox found the germiest place in your car is the driver’s side floor mat.)
Now that public health officials are recommending that we all wear high-performance, medical-style masks, known as respirators — N95s, KN95s and KF94s — mask care is more important than ever. Unlike with cloth masks, you can’t toss a medical-style mask in the laundry. And high-performance masks cost more — $30 or more for a set of 10 — so it’s important to know how to reuse them.
Unfortunately, there’s very little official guidance for how to care for and reuse a high-performance mask.
The Centers for Disease Control and Prevention has said health workers coping with mask shortages can reuse respirator masks up to five times. But the average person wears a mask for much shorter periods and can safely reuse a mask many more times, said Linsey Marr, a professor of civil and environmental engineering at Virginia Tech and an expert on viral transmission.
“The existing guidance on respirator care is for health workers and other workers who use respirators in hazardous conditions,” Marr said in an email. “For the general public, the conditions (typically not in close contact with infected patients for much of the day) and expectations (a person trying to reduce their risk of infection while going about their daily life) are much different, and I don’t think we should apply the same guidance to the two groups.”
Still, the CDC guidance can provide a useful framework to help us make decisions about how long to use a mask. Based on the five-day rule for health workers and assuming they wear the mask throughout an eight-hour shift, that suggests about 40 hours of use per mask, said Anne Miller, executive director at Project N95, a nonprofit that vets and sells high-performance masks. Many of us wear a mask in 15- and 30-minute increments, which means one mask could last weeks.
Realistically, if you’re taking a mask on and off frequently, your mask will most likely become soiled or the straps will break before you hit the 40-hour mark.
“I don’t wear my respirator all day long — I go to the grocery store and come back,” Miller said. “I find that I end up dropping them in the snow or the floor of the car before I wear them out. Usually the straps wear out before the respiratory capability wears out.”
Never try to clean your high-performance mask. While it may feel like synthetic fabric, respirator medical-style masks are made of layers of high-tech filters that have been electrostatically charged to better attract and trap particles. Washing a mask, or trying to sanitize it with alcohol, peroxide or even ultraviolet light will degrade it and make it less effective. Just let your mask air out on a hook, in a bag or on a clean shelf.