HAMILTON, Ontario — As the world battles the coronavirus pandemic, wearing a face mask has become as natural as putting on pants. Months into the crisis however, the debate over which mask is best to protect against infection is still going. An international research team is now making the case for cloth to prevent the spread of COVID-19.
Researchers suggest cotton cloth masks with several layers of protection are the best option. That’s especially true for keeping the wearer’s germs away from other people.
“The point is not that some particles can penetrate the mask, but that some particles are stopped, particularly outwardly, from the wearer,” Catherine Clase of McMaster University said in a statement.
Cloth Masks? “Old” News
Clase and her team weren’t just looking at recent data on the COVID-19 outbreak, the study found evidence cloth is the best way to stop contamination dating back over the last 100 years.
Similar studies done in the 1960’s and 70’s revealed that a three-layer mask, made of cotton-muslin and flannel, could stop 99 percent of contaminations from surfaces and airborne micro-organisms. They also stopped most smaller particles, known as aerosols, which are one of the main ways COVID-19 is spread.
“Public-health decisions about public mask wearing have been difficult to make, and why they differ around the world,” Clase added. “Our review suggests that cloth can block particles, even aerosol-sized particles, and this supports Canadian public health policy on the issue.”
And The Winner Is…
The study says that a four-layer mask made of cotton muslin can reduce contamination of all particles by 99 percent. A present day, disposable medical mask was found to block between 96 and 99 percent of particles. Even with the tiny aerosol particles, a cloth mask was found to be just as effective as a standard medical mask.
Researchers add that if you’re using items like a scarf or shirt as a makeshift mask, it’s important to layer up. A single layer of cloth was found to stop between 10 and 40 percent of particles. Some fabrics were found to do a better job than others, like cotton-flannel, which researchers say can stop over 90 percent of particles.
“In terms of making masks, it is important to realize that more layers will give more protection, both inward and outward, but will make it harder to breathe,” Clase explained.
The study recommends that children under two and anyone with respiratory problems avoid wearing a mask that could obstruct there breathing.
The team’s research on masks was published in the Annals of Internal Medicine.