(July 3, 2020) – Three of the five most effective cloth face coverings tested by the National Institute of Standards and Technology were 100 percent cotton and had a visible raised fiber or nap, such as found on flannels, the agency
announced this week. The researchers tested how well 32 natural and synthetic fabrics filtered particles similar in size to the virus that causes COVID-19; none of them came close to the efficiency of N95 masks. The Centers for Disease Control and Prevention recommends
people wear cloth face coverings to help protect others in public settings where social distancing is difficult.