It is intuitive that a barrier ought to prevent germs from being emitted into the air. But if that’s true, why isn’t there more evidence for the benefits of masking two years into the pandemic? Experts associated with The Center for Infectious Disease Research and Policy (CIDRAP) at the University of Minnesota have laid out a more complex analysis: Given the current understanding that the virus is transmitted in fine aerosol particles, it’s likely an infectious dose could easily get through and around loose-fitting cloth or surgical masks.

Many experts say only N95 respirators or similar devices are truly effective at stopping this virus — and some, such as the CIDRAP head Michael Osterholm, have been going public urging people to put less faith in cloth masks and adopt respirators such as N95s. He does not advocate universal N95 use in schools, however, where children are unlikely to be able to wear them consistently or correctly.

Most of the people who were only wearing masks because of the mandate were donning the less effective masks. Those concerned enough to get an N95 aren’t going to stop because it’s not required. Future policies should focus on helping people understand their risks and making sure everyone who wants a supply of N95 masks can get one.