№ 546. Not All Masks Are Created Equal

Is there a hierarchy of masks?
 

A new study in Duke University ranked 14 types of commonly available masks, finding that medical masks offer significantly more protection against droplet spread than cotton alternatives – while bandanas protect less, and neck fleeces don’t do much at all.
 

The study revealed that different masks eliminated droplet spray by the following percentages, from the best to worst:

1. N95 - 99.9%
2. Surgical or polypropylene masks - 90%
3. Cotton face coverings - 70% to 90%
4. Bandanas - 50%
   

Neck fleeces, meanwhile, were found to expel more droplets than with no mask at all, probably by dispersing the largest droplets into many smaller droplets.

"The notion that 'anything is better than nothing' didn't hold true," said Eric Westman, one of the study's co-authors.