What Type of Face Covering Should I Wear?

By Catherine M. Fascilla, D.D.S.

With the increase in air pollution and especially with the recent spread of COVID-19, people are seen throughout our nation and throughout the world wearing various types of facial coverings. Our governor mandated that we do so on April 17, 2020. The scramble to buy masks have resulted in shortages and have lead to people sewing their own and to some U.S. companies redirecting their efforts and their resources to manufacturing them.

As we try to cover our faces with whatever we can get our hands on, do we understand what we are doing, why we are doing it and whether or not our face covering is accomplishing the task. It is my objective to help clarify these points.

Before the Coronavirus pandemic, “masks” were used in the work setting. The word is being used as a generic term for various types of face coverings most commonly used in the medical or industrial fields. A mask covers both the nose and the mouth to create a barrier and to filter out a pollutant. It is often stamped with different letters and numbers which give information about its capabilities.

All masks are made of different layers designed for stopping a different pollutant. The primary filter is the outer layer that blocks large particles like dust and pollen. Because the particles are ten microns or greater you may see PM10 noted on the mask. PM10 stands for particulate matter no smaller than ten microns. The second layer is a particle filter that is added to filter even smaller particles. PM2.5 means the filter can trap or block particles up to 2.5 microns. Some high-end masks may also contain a carbon filter. Only a carbon filter can filter out gaseous pollutants and the device might be marked with a C. So those are the filter layers that are used to make a mask.

There are many types of devices or “masks” that are used to protect a person from breathing in harmful chemicals, particles or germs. The most common are the surgical masks and the respirators.

Surgical masks are what you typically see a doctor, nurse or dentist wearing. They are rectangular-shaped, pleated, made of relatively thin and soft non-woven material that is loosely fitted against the face with a metal bar over the nose to secure its fit and ear loop to hold it in place. While available in several colors, they are most often blue. By design, they are created to protect the patient in a surgical setting. They help contain the wearers bacteria and germs from contaminating a sterile field. They will also block and protect the wearer from large droplets, splashes and splatter that may contain germs.

Respirators are commonly worn by construction workers and by medical personnel who are treating patients who potentially have COVID-19. This is a cup-like device that is made of a thicker stronger almost cardboard-like material that fits firmly against the face to create a snug and tight seal. These masks are designed to filter smaller particles from the air and to reduce the number of germs the wearer breaths in. They are stamped with NIOSH, a devision of the Center for Disease Control and Prevention (CDC) and will also have a rating on it, like N95, N99, or N100. Instead of the N, it could be another letter like R or P.

The numbers signify the amount of particles up to .3 microns in size that can be filtered. A respirator marked 95 will filter 95 percent of the particles that are .3 microns. A respirator marked 99 will filter 99 percent and 100 filters 99.9 percent. That is great for filtering most pollutants, bacteria and mold but viruses are smaller than that (between .005 and .3 microns). The filtration rate for virus particles will likely be less than 95 percent.

The letters tell us if the respirator can filter oil-based pollutants. N means no oil-based pollutants will be blocked. It can only block airborne particulate. R means the device is oil resistant. In addition to airborne particulate, it will block oil-based pollutants to some extent. P means the respirator is oil proof. It will block oil based pollutants and airborne particulate.

So if you are concerned about pollution, a respirator should be worn rather than a face mask. N95 is usually the most available and least expensive of all of the classifications discussed. N99 and N100 are more expensive and more difficult to find than N95. R and P rated respirators are even more expensive and difficult to come by than N rated respirators. If you are trying to be in compliance with the most recent governmental mandates pertaining to the coronavirus pandemic, then a simple cloth face covering is what is recommended by the CDC. In order to slow the spread of COVID-19, face coverings are to be worn in public settings where social distancing can not be maintained like in a grocery store, and on a crowded sidewalk or train. This is particularly important in areas of significant community-based transmissions like in the state of NY. Governor Cuomo wants all New Yorkers, two and older who are medically able, to cover their faces when they can not maintain a six foot distance in public. But the CDC does not recommend that the face covering be a surgical mask or a respirator because those are critical supplies that must be reserved for healthcare workers and other medical responders.

The CDC is a valuable resource for COVID-19 information. On their website you can find instructions to make your own face covering that you can either sew or simply cut from fabric. The website states that the covering should fit snugly and comfortably against the face, be secured with ties or ear loops, include multiple layers of fabric, allow for breathing without restriction and be able to be laundered and machine dried. The tighter the knit of fabric the better and a non-woven fabric is better than a woven fabric. Some of the home made masks call for multiple layers of fabric with an opening between the layers for the placement of a piece of paper towel or coffee filter.

All of these coverings helps to reduce the amount of exposure. But remember, no face covering, mask or respirator is full proof to prevent a coronavirus infection. The best method to avoid illness is to avoid contact with the virus. Maintain distance, wash your hands and keep your hands away from your face. And very importantly, keep your immune system healthy and strong by eating well, exercising and by getting enough rest. Let’s leave the surgical masks and respirators to the workers that need them.

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