A surgical mask is a loose-fitting, disposable mask that’s rectangular in shape. The mask has elastic bands or ties that can be looped behind your ears or tied behind your head to hold it in place. A metal strip may be present at the top of the mask and can be pinched to fit the mask around your nose.

A properly worn three-ply surgical mask may help block transmission of large-particle microorganisms from droplets, sprays, splatters, and splashes. The mask may also reduce the likelihood of hand-to-face contact.

The surgical mask’s three-ply layers work as follows:

• The outer layer repels water, blood, and other body fluids.
• The middle layer filters certain pathogens.
• The inner layer absorbs moisture and sweat from exhaled air.

However, the edges of surgical masks don’t form a tight seal around your nose or mouth. Therefore, they can’t filter out small airborne particles such as those transmitted by coughing or sneezing.

The World Health Organization (WHO)Trusted Source recommends using surgical masks only if you:

• have a fever, cough, or other respiratory symptoms
• are well but caring for someone with a respiratory illness — in this case, wear a mask when you’re within 6 feet or closer to the person who is ill

Although a surgical mask helps trap larger respiratory droplets, it can’t protect you from contracting the novel coronavirus, which is known as SARS-CoV-2. That’s because surgical masks:

• don’t filter out smaller airborne particles
• don’t fit snugly on your face, so airborne particles can leak in through the sides of the mask

Some studies have failed to show that surgical masks effectively prevent exposure to infectious diseases in community or public settings.

At present, the Centers for Disease Control and Prevention (CDC)Trusted Source doesn’t recommend that the general public wear surgical masks or N95 respirators to protect from respiratory illnesses like COVID-19. Healthcare providers and first responders need these supplies, and there’s currently a shortage of them.

However, in the case of COVID-19, the CDC does advise the general public to wear cloth face coverings to prevent the spread of the disease. The CDC also provides instructionsTrusted Source on how to make your own.

If you need to wear a surgical mask, take the following steps to put one on correctly.

Once the mask is positioned securely, there are certain precautions to keep in mind to ensure you don’t transfer pathogens to your face or hands.

It’s important to remove the face mask correctly to ensure you don’t transfer any germs to your hands or face. You also want to make sure you discard the mask safely.

N95 respirators are form-fitted to the size and shape of your face. Because they fit your face more snugly, there’s less opportunity for airborne particles to leak in around the sides of the mask.

N95s can also filtrate small airborne particles more effectivelyTrusted Source.

The key to an effective N95 is to ensure that it fits your face correctly. Healthcare practitioners who provide direct patient care are fit-tested annually by a qualified professional to be sure their N95 fits them snugly.

A properly fitted N95 respirator usually filtrates pathogens in the air much better than a surgical mask. Respirators that have been carefully tested and certified to carry the N95 designation can block up to 95 percentTrusted Source of tiny (0.3 micron) test particles. But they also have their limitations.

However, the Food and Drug Administration (FDA)Trusted Source doesn’t recommend that the general public use N95 respirators to protect themselves from respiratory illnesses such as COVID-19. If worn without a snug fit, they can’t filter out small airborne particles that cause illnesses.

According to the FDA, the best way to prevent an infection is to avoid being exposed to the virus. It recommends practicing social distancing and frequent handwashing.

The results of a 2016 systematic reviewTrusted Source and meta-analysis found no significant difference between N95 respirators and surgical masks when used by healthcare workers to prevent transmission of acute respiratory infections in clinical settings.

A recent 2019 randomized clinical trial published in the journal JAMA supported these findings.

If you have a respiratory illness, the best way to minimize transmission is to avoid other people. The same applies if you want to avoid contracting a virus.

To reduce your risk of transmitting the virus, or coming into contact with it, the WHOTrusted Source recommends the following:

• Practice good hand hygiene by washing your hands frequently with soap and water for at least 20 seconds at a time.
• Use hand sanitizer that contains at least 60 percent alcoholTrusted Source if you don’t have access to soap and water.
• Avoid touching your face, mouth, and eyes.
• Keep a safe distance from others. The CDCTrusted Source recommends at least 6 feet.
• Avoid public places until you recover fully.
• Stay home and rest.

Surgical masks may protect against larger airborne particles, while N95 respirators provide better protection against smaller particles.

Putting on and taking off these face masks correctly may help protect you and the health of those around you from transmitting or contracting pathogens.

Although face masks may help reduce the spread of some disease-causing organisms, evidence suggests that using face masks may not always protect you or others from exposure to certain pathogens.