Wearing two tightly-fitted face masks can keep Covid spread in check SECTIONS Last Updated: Apr 19, 2021, 06:58 PM IST Share iStock Related NEW DELHI: Wearing two tightly-fitted face masks can nearly double the effectiveness of filtering out SARS-CoV-2-sized particles, preventing them from reaching the wearer's nose and mouth and causing COVID-19, according to a study. The research, published in the journal JAMA Internal Medicine, shows that the reason for the enhanced filtration is not so much adding layers of cloth, but eliminating any gaps or poor-fitting areas of a mask. "The medical procedure masks are designed to have very good filtration potential based on their material, but the way they fit our faces isn't perfect," said Emily Sickbert-Bennett, an associate professor at the University of North Carolina (UNC) in the US, and lead author of the study.