A new CDC report suggests ways to increase the effectiveness of masks in slowing the spread of COVID-19.
The CDC conducted experiments to assess two ways of improving masks and both helped:
- using two masks – a cloth mask over a surgical mask, or
- knotting the ear loops of a surgical mask and then tucking in and flattening the extra material close to the face (click here for a video demonstration of this method).
According to the report, “each modification substantially improved source control and reduced wearer exposure.”
Specifically, in lab tests, exposure to potentially infectious aerosols decreased by about 95% when people wore tightly fitted masks.
Getting the right mask fit
The CDC says other studies show there are multiple ways to get a better mask fit, including:
- using solid or elastic mask fitters worn over the mask, or
- placing a sleeve made of sheer nylon stockings around the neck and pulling it up over either a cloth or surgical mask.
The new call for double-masking is explained in an article in the CDC Feb. 10 publication of Morbidity and Mortality Weekly Report (MMWR).