The short answer from an infectious disease specialist
Q: Is double masking more effective at preventing the spread of COVID-19?
A: The Centers for Disease Control and Prevention recommends universal mask wearing as an important way to slow the spread of COVID-19.
At this time, the CDC recommends wearing a face mask with two to three layers that fits snugly over your face. The CDC recently published new research suggesting that layering a cloth mask over a surgical mask (double masking) when a mask only has one layer, or knotting and tucking a single mask, may improve the fit of masks and provide additional protection from potentially infectious particles.
However, if your mask already has multiple layers and fits tightly, it’s not necessary to double mask.
Source: Gordon, Steven MD, February 12, 2021, Should You Wear Two Masks to Prevent the Spread of COVID-19?, Retrieved from Cleveland Clinic
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