Can You Rely On Your Medical Mask?

mask usage

In the 2020 flu season, there was very little influenza circulating. However, the 2021 flu season could be quite different, largely because there are fewer restrictions in place. Not only will we see a continued spread of the Delta variant of COVID, but we also expect other respiratory viruses to be spreading. In British Columbia, that means we still need to observe standard protective measures, such as hand washing and wearing masks in public spaces.

How do you know that the mask you are wearing is providing effective protection?

Many disposable masks that you find in a retail store have no rating scale to verify how effectively they filter out particles. The International Association for Testing Materials sets standards for various materials. There are five testing criteria for surgical masks:

  1. Bacterial filtration efficiency;
  2. Sub-micron particulate filtration efficiency;
  3. Differential pressure for inhalation;
  4. Resistance to synthetic blood; and
  5. Flame resistance.

According to Sidney R. Siu, an Occupational and Environmental Medicine Specialist at Western University, there are three ASTM levels for surgical masks. “Level 1 requires a 95% filtration efficacy, while Levels 2 and 3 require 98%. Level 3 provides better slightly better fluid resistance.” As such, an ASTM Level 3 mask is more suitable in a lab setting, while an ASTM Level 2 mask provides very reliable filtration to protect mask wearers in a community setting. A CBC Marketplace study from Nov 2020 found that disposable 3-ply surgical masks reported some of the highest filtration efficiency rates of all mask types tested. Their interwoven fibre matrix stops more airborne particles than woven material (as in cloth masks).

What about N95 respirators?

N95 respirators are the only masks that can completely protect against airborne illnesses such as COVID. These are not the N95 masks that you find in retail stores. N95 masks, such as those used in dental offices (where high-level spray requires a greater level of protection) need to be fitted to the individual, based on tests that identify the size and style of mask that will be suited to the wearer’s face. Since these are used in specific circumstances and require fitting, N95 masks are available only through medical suppliers.

Are you wearing your mask properly?

If your mask slides around or is not fitting properly over the nose and under the chin, it will not block aerosol particles as it is meant to. Here’s a quick reminder of the steps to put on and remove your medical mask:

  1. Prior to handling your mask, wash your hands or use hand sanitizer.
  2. Remove the mask from the box, grabbing from the ear loops or side of the mask.
  3. Do not touch the inside of the mask, and make sure the coloured side is facing out.
  4. Secure ear loops around the ears.
  5. Pinch the nose bridge to create a seal and to keep mask from sliding around.
  6. Stretch the mask down at the middle to cover your chin and create a seal at the bottom.
  7. Avoid touching your mask while wearing it. If you do, wash your hands or use hand sanitizer again before touching anything else.
  8. To remove your mask, grab the mask by the ear loops only and drop the mask in the trash without touching the outer layer.

Will a mask protect you from COVID and the seasonal flu?

It is important to remember that masks are worn mostly to keep other people safe, by limiting the spread of any respiratory virus that you may be carrying. An ASTM-rated medical mask will offer moderate barrier protection from low to moderate levels of aerosols, spray and fluids.

Wearing a mask and staying up-to-date on your vaccinations will provide the best level of protection for you and those around you. You can book an appointment at Medicine Shoppe Pharmacy in Courtenay to get your seasonal flu vaccination and other immunizations. Online booking is available at We wear ASTM Level 2 masks in our pharmacy and have a supply available for purchase ($14.99 per box/50).

Stay healthy.

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