During my (limited) ventures outside of home or the College, it’s getting more common to see people walking around wearing nose-and-mouth masks.

My first thought is “Where are you getting those? They’re short in supply.”

My next thought is “Stop wasting masks! You don’t need them.”

My last one is “At least wear it right! I can see your nose!!!”

The obvious question is, should people wandering around town wear masks at all?  The short answer is NO.

Outside of medical procedures, surgical masks (and similar nose-and-mouth masks) are used mainly to prevent an infected person from spreading infectious droplets when they cough or talk. So, if someone was sick, it would help protect people around them. However, if they’re sick, they should be at home, not out in public.

Masks are less effective for protecting the average person walking down the street.  The main benefit is probably preventing someone from touching their own mouth or nose and transferring whatever is on their hands to their mucous membranes. So it’s not entirely pointless, but the degree of benefit in this scenario is limited, and when masks are in short supply in many areas this is certainly not the best use of a scarce resource.

Recommendations from different areas vary a bit but in general, there’s limited support for mask use in the community. Here’s a table from a Lancet paper that compares several of these guidelines (Feng et al 2020).

So, if you’re walking around town, working in an office or doing anything else in public, you’re better off paying attention to hand hygiene (and just not touching your face) than wearing (and wasting) a mask.