Public Health Agency of Canada now recommends three-layer masks

A large spike in COVID-19 cases across the country is one of the reasons for the latest public health suggestion

PHOTO: Kai Pilger / Unsplash

Written by: Sara Wong, Peak Associate 

During a press conference on November 3, Canada’s Chief Public Health Officer Dr. Theresa Tam updated recommendations surrounding the wearing of non-medical masks and recommended that the public use three-layer masks. According to the Public Health Agency of Canada (PHAC), two of these masks’ layers should be a tightly-woven material (like cotton) and the extra layer should act as a filter, using a “non-woven polypropylene fabric.” 

If you have a mask with a pocket, you can insert a removable filter into it and that can serve as the third layer. The PHAC recommends craft fabric, a piece of a reusable shopping bag, or a folded paper towel as options for a filter. Depending on the material, the filter can be washed and re-used or will have to be disposed of and replaced frequently. Additionally, the PHAC provided step-by-step tutorials on its website on how to create your own three-layer mask, with choices between “sew method,” “no-sew method using a T-shirt,” and “no-sew method using a fabric square.”

According to Dr. Jing Wang, a clinical instructor in UBC’s faculty of medicine, the PHAC’s changes in mask recommendations are a result of the rise in COVID-19 cases across the country. On November 12, CTV News stated that “Canada reported 4,981 new cases of COVID-19,” which broke the country’s record for the largest single-day total of COVID-19 cases. At the time of writing, this remains Canada’s highest daily record. 

Dr. Tam spoke at another press conference, in which she warned the public that case numbers will continue to increase by the thousands if people do not do their part to stop the spread. Global News quoted Dr. Tam on how “an important driver continues to be informal social gatherings, and activities both inside and outside our homes” in regards to rising COVID-19 cases.

Another reason for the three-layer mask recommendation is because COVID-19 can be transmitted by aerosols as well as droplets. The difference between the two is that aerosols are smaller and can linger in the air for some time. Additionally, with winter approaching and many activities moving indoors, it is imperative to maximize ventilation in order to decrease concentrations of aerosols, as noted by the PHAC. Wearing face masks while indoors (excluding your own household) is advised.

A number of Canadian news outlets have pointed out that the World Health Organization (WHO) recommended three layer masks back in June, causing reporters to question why the PHAC waited months before following suit. In a statement given to the Toronto Star, the PHAC said that “[they] always work to do [their] own analysis to determine what is appropriate for Canadians, rather than just accept recommendations from the WHO or other organizations.” 

Regardless of the type of mask, Dr. Tam emphasized that in order to be of any protection, masks need to fit properly. Quoted first by CTV News, Dr. Tam stressed that “[a mask] has to cover your mouth and nose [ . . . ] that’s really important.” 

As of November 19, masks have been made mandatory in BC “for all customers and workers [ . . . ] in all indoor public and retail spaces, including hallways, elevators, breakrooms, kitchens, and customer counters. The only exception is while eating or drinking.” For more information on COVID-19, visit the BC Centre for Disease Control’s website.