Al Jazeera, February 2021
Wearing two masks at once can offer more protection against potential coronavirus transmission and exposure than donning a single mask, the US Centers for Disease Control and Prevention (CDC) has advised. In a report published this week, CDC researchers said exposure to potentially infectious aerosols decreased by about 95 percent when a cloth mask was worn over a medical procedure mask, a practice also known as double-masking.
To provide the same protection, a mask can also be worn by knotting the ear loops of a medical procedure mask and then tucking in and flattening any extra material close to the face. The key, the report found, is to ensure the masks fit tightly. “Medical procedure masks are intended to provide source control (eg, maintain the sterility of a surgical field) and to block splashes,” it said.
As new, more virulent strains of COVID-19 have emerged in countries around the world, many public figures have been seen wearing two face masks instead of one, including US President Joe Biden. The country’s top infectious disease expert, Dr Anthony Fauci, has called it “common sense” to wear two masks. “This is a physical covering to prevent droplets and virus to get in,” Fauci told NBC’s Today show.