12 h, mar 28, 2020 y - CDC: "You do not need to wear a facemask unless you are caring for someone who is sick (and they are not able to wear a facemask)."
Description:
https://web.archive.org/web/20200328172009/https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/prevention.htmlAdded to timeline:
Date:
12 h, mar 28, 2020 y
Now
~ 5 years and 6 months ago