Currently, Canadians have embraced wearing face masks which come in all shapes, sizes and styles. They range from one-use surgical masks to brightly patterned cloth masks. However, every mask provides a different level of protection to the wearer. Health officials, countries, cities and airlines are discouraging the use of masks with an exhaust valve.
You could have seen masks with additional raised plastic valve, around the size of a quarter. These valves are known as respirator valves, exhalation valves or exhaust valves. Though N95s are very useful masks, some have these valves. Wearing masks with a valve will do little to prevent the spread of COVID-19, according to Health Canada’s website.
The health agency indicates that several commercially available respirators have exhaust valves which allow infectious respiratory droplets to be released outside the respirator as they are intended to make the respirator more comfortable for the person wearing it. These valves open to allow the exhalation to escape and prevent the buildup of heat and bacteria on the inside of the mask. The masks are essential in protecting people from inhaling dust while doing some DIY renovation of your kitchen. People are advised not to use respirators with exhaust as they will not be protected from COVID-19.
Health officials keep on saying that the primary aim of wearing face masks is to protect others from you, not the other way around. The aim of wearing a face mask is to cut down on droplets expelled from a person’s mouth when they breathe, sneeze or cough. They may provide more protection from contracting the virus than not wearing one. According to health experts, the main way the virus spreads is through droplets sprayed from a person infected with COVID-19. Moreover, infected people can spread the virus before they exhibit symptoms or if they’re asymptomatic. This means that potentially dangerous droplets can escape into the air through valves that allow the exhalation to pass through without being filtered through the mask.
Dr. Rhonda Low, a Vancouver-based family physician, confirmed that these masks could even make an exhalation more dangerous than without a mask. A recent study revealed that the presence of a valve on an N95 that they tested made it significantly less effective than a fitted N95 with no valve. The study reads, “The performance of the valved N95 mask is likely affected by the exhalation valve, which opens for strong outwards airflow. “While the valve does not compromise the protection of the wearer, it can decrease protection of persons surrounding the wearer.”
Many cities within Canada are asking residents to stay away from masks with valves. Toronto Public Health has put up factsheet on masks that stipulates that masks with exhalation valves are prohibited. They say the valves “may filter dust particles in the air as the person inhales, but they may not filter virus particles or respiratory droplets.” Face masks are mandatory in Toronto in indoor areas. Besides, Ottawa Public Health also specifies that masks with exhalation valves are not recommended.
In late June, the B.C. Centre for Disease Control gave recommendations on face masks where they indicated that “industrial N95 respirators” were not recommended as they have valves. The U.S. Centers for Disease Control and Prevention has also asked people not to use respirators with exhalation valves. They confirmed that these masks “should not be used in situations where a sterile field must be maintained” like in a hospital setting.
In San Francisco, California, masks with valves have been included on their list of face coverings that do not comply with the regulations. The authority requires wearing of masks in all businesses, and anytime a person comes within 6 feet of someone outside of their household. In May, Denver, Colorado, stated that all masks with one-way valves could not be counted as proper face coverings under the order requiring individuals to wear masks in public. Besides, most airlines in the U.S. have banned face masks with exhaust valves.