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John Volckens Profile picture
John Volckens
@Smogdr
Fighting air pollution one particle at a time. This might take a while...
Feb 19, 2021 • 7 tweets • 5 min read
1/ Our new @EnvSciTech paper on #mask performance. Take-home stuff follows:

Quantitative Protection Factors for Common Masks and Face Coverings pubs.acs.org/doi/10.1021/ac… 2/ Most cloth masks have poor efficacy for aerosol <1 micron. The 7 #masks we tested are in use worldwide and were supplied by @WHO. Mask E is a KN95.