Cloth masks fall short in Covid protection

"Several studies show that cloth masks are mainly used for outside use with minimum interaction or capacity. They only work to their best ability if they are made out of two-layer tight-weave cotton. Made properly, they can only filter out about 35% of small particles."

Posted Oct. 5, 2021

By Natalie Hebert

Staff Reporter


During the Covid stir, there was a shortage of disposable masks, so people decided to make or buy masks made of cloth. But is using a cloth mask still the same as a disposable one? The answer is no.

Several studies show that cloth masks are mainly used for outside use with minimum interaction or capacity. They only work to their best ability if they are made out of two-layer tight-weave cotton. Made properly, they can filter out about 35% of small particles. Adding a filter made out of two layers of charged polypropylene could boost the filtration efficiency by 35%. In order to reuse the filtered cloth mask, however, it must be ironed or rubbed to gain its electrostatic charge that it lost in the wash. That means cloth masks must be washed in order to keep using them. These masks are made in several different colors and patterns, but that makes it difficult to match with outfits and to complete the whole style.

Surgical masks, or disposable masks, were in short supply at the start of the pandemic, causing cloth masks to be made or bought more regularly. Surgical masks are made to protect other people from the majority of the wearer's large particle droplets, splashes, or sprays of bodily fluid. Even though they don’t block small particles, some filter around 30% and others filter out as much as 80%. Many surgical masks are made of paper, though some are made with polypropylene. Disposable masks are easy to discard and come in only certain colors that look great with every outfit.

There are other alternatives that are better than cloth and disposable, such as the N95 respirators. They block at least 95% of small particles that protect both the wearer and the people around them. Another type is KN95 respirators that are supposed to filter out at least 95% of small particles, but data shows that the masks are not consistent. N95s and KN95s remain in short supply and should be reserved for health care workers and first responders.