N95 masks and surgical masks should be disposed of after one use.
  • Unlike cloth face masks, disposable masks like surgical masks and N95 respirators should be thrown out after one use. 
  • As a last-resort measure in emergency situations, it is possible to extend the life of a disposable face mask if extreme care is taken. 
  • If you use a reusable mask, make sure to wash it once a day and consider a double-mask with two-to three layers of fabric, for added protection.
  • Visit Insider's Health Reference library for more advice.

Whether or not you should reuse a face mask depends on the type of mask. 

Can you reuse a breathable, washable cloth mask? Yes, no problem. Just follow these CDC guidelines on how to wash a cloth mask.

But what about a disposable mask, like medical-grade surgical masks and N95 respirators? 

The short answer: You should not reuse disposable masks per CDC and WHO advice.

However, if we learned anything from the dire mask shortage from early in the COVID-19 pandemic, it is possible. Here's what you need to know. 

Why N95 and surgical masks should not be reused 

The two most common types of disposable masks - medical-grade surgical masks and N95 respirators - also happen to be the most effective type of mask in preventing infection, which explains why the CDC recommends they be reserved for medical and frontline workers. 

However, these masks are most effective during first-time use, which is why you should not reuse them. If reused, these masks can actually increase your risk of infection because of how they work:

  • Surgical masks are loose-fitting face coverings that act as barriers to protect the mouth and nose from potential contaminants, typically used by medical professionals as personal protective equipment (PPE). They can also be used by sick patients to minimize the spread of disease from large-particle droplets that are coughed and breathed out.
  • N95 respirators are tight-fitting masks that filter out at least 95% of the particles in the air in order to minimize the wearer's exposure to viruses and bacteria. They're worn by healthcare workers and first responders who are caring for the sick and don't want to get infected. 

Because these masks act as a physical barrier against respiratory droplets and germs, they can also transfer those particles onto other surfaces. This makes disposable masks a potential hazard in spreading and transmitting disease if reused or not properly discarded.

Guidelines for reusing disposable masks in emergency situations

You should avoid reusing disposable masks as much as possible.  However, if you're in an emergency situation, here's what you can do to minimize infection: 

  • Be careful when taking the mask off. If you need to adjust your mask, make sure you wash your hands before you do or use a hand sanitizer that has at least 60% alcohol in it. When taking your mask off, make sure to do so by the straps and avoid touching the actual mask directly. 
  • Make sure you're storing your mask in a clean, breathable area. Avoid putting your mask on dirty surfaces, including inside your purse, on an uncleaned surface, or holding it in your hand. When not in use, the mask should be stored in a breathable container, like a paper bag or open tupperware container. Plastic bags or other storage containers that seal off air completely should not be used. 
  • Only reuse your mask. A surgical mask or N95 respirator should only be reused by the same person, never shared between others.
  • Extended use is better than reuse. It's better to leave a respirator on for the whole shift rather than taking it on and off. This minimizes contact between your hands, the mask, and other surfaces thereby reducing the risk of spreading infectious particles. The CDC guidelines say that there's no way to predict a safe number of reuses, so medical professionals should use their judgement.
  • If you absolutely have to reuse a disposable mask, sanitize the mask as much as you can first. A 2020 study by the NIH found that you can sanitize N95 masks using UV rays (a form of light)  and vaporized hydrogen peroxide to effectively disinfect a mask. As a rule of thumb, you should avoid using a liquid disinfectant as it could cause harm if you inhale it.

Surgical masks and respirators don't suddenly expire, although their fibers and elastics bands - which are important for getting a snug fit - can deteriorate over time. Hans Rechsteiner, MD, a general surgeon at Burnett Medical Center estimates that masks are at their best within five years of manufacture, although an older mask is certainly better than nothing. 

You should also throw out masks (reusable or disposable) that have any holes or damage that could compromise their effectiveness. Soiled masks should also be thrown out. 

What masks can I reuse?

If you can wash a mask with water and soap frequently without  damaging it, you can reuse it. This includes store-bought cloth masks and homemade masks. It's worth noting that if you are making your own mask, the CDC's guidelines urge you to make sure the mask fits snuggly on the face and that it fully covers your mouth and nose.

General tips for proper mask usage

    • Always wash your hands before handling the mask: Use a hand sanitizer with 60% alcohol or soap and warm water to wash your hands before removing or adjusting your mask. 
    • Whether reusable or disposable, do not touch the mask: Use strings, loops, or straps that keep your mask fastened to your ears/head to remove the mask. 
    • Designate a clean space to keep your masks when not in use: It's important to think about storing your masks in a sanitized, breathable environment. This applies at home and on-the-go. 
    • Dispose of surgical and N95 masks after one use: If a surgical mask is damp, that's generally an indication you should switch it out for a new one. 
    • For cloth masks, aim to wash it after every use: Wash your mask on high heat using soap and water. According to WHO, heat of 133°F can kill the coronavirus. If your mask has a filter, make sure to remove it before washing and replace it with a new one after.
    • When disposing of your mask, cut off the strings: Early research indicates that disposable masks may pose an environmental issue. Additionally, some anecdotal reports have shown that animals like birds can get trapped in or choke on surgical masks. For this reason, cutting off the strings of the mask before disposing of them reduces the risk of animal harm. 
    • Double-masking can provide extra protection: In order to provide an extra layer of protection with masks, you can use three layers of cloth to create a more secure barrier.This could look like a cloth mask and a surgical mask, or a cloth mask that has three layers sewn in. 

Insider's takeaway

Wearing a mask is necessary to reduce exposure to and infection from air-borne diseases like COVID-19. However, if not worn properly, they won't be effective. 

Surgical masks and N95 masks are disposable medical grade masks that are the most effective in keeping out viruses and bacteria. They should be thrown out after one use and reserved for healthcare workers. 

Cloth masks and other homemade masks, while not as effective as medical masks, can be washed and reused. Make sure to wash them after each use with high heat and soap, and remove any filters while replacing them with new ones. 

If daily washing doesn't fit in your schedule, rotate between multiple masks in between wash cycles. 

"If you want to be extra safe, use three masks and rotate them daily, letting them sit out in a well-ventilated area to dry in the meantime so that the viruses die," Rechsteiner, says. "Because of severe shortages in some areas I believe that this is a safe and acceptable practice."

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