HOUSTON – The Centers for Disease Control and Prevention issued a report Wednesday that called for double masking in an effort to slow the spread of the coronavirus.
The report said double masking – a combination of a cloth mask and a medical procedure mask – blocked 92.5% of cough particles.
The report also urged the importance of improving the fit of medical procedure masks by double masking, knotting ear loops and tucking in and flattening the extra material close to the face.
“Each modification substantially improved source control and reduced wearer exposure,” the report reads.
“These laboratory-based experiments highlight the importance of good fit to maximize overall mask performance,” the report continues. “Medical procedure masks are intended to provide source control (e.g., maintain the sterility of a surgical field) and to block splashes. The extent to which they reduce exhalation and inhalation of particles in the aerosol size range varies substantially, in part because air can leak around their edges, especially through the side gaps. The reduction in simulated inhalational exposure observed for the medical procedure mask in this report was lower than reductions reported in studies of other medical procedure masks that were assessed under similar experimental conditions, likely because of substantial air leakage around the edges of the mask used here.”
Some limitations, such as the number of masks available on the market, facial hair and other factors were listed in the report. Read it in full here.
The government report said until vaccine population immunity is achieved “universal masking” is a highly effective means to slow the spread of the coronavirus when combined with physical distancing, avoiding crowds and poorly ventilated indoor spaces, and good hand hygiene.
“The data in this report underscore the finding that good fit can increase overall mask efficiency,” the report concludes. “Multiple simple ways to improve fit have been demonstrated to be effective. Continued innovative efforts to improve the fit of cloth and medical procedure masks to enhance their performance merit attention.”