Sorry to send so many emails but it seems helpful to keep the subjects separate.
The CDC has interim guidance on safety measures for essential personnel who have had potential exposure here:
How to wear and make face masks – https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/diy-cloth-face-coverings.html
Please remember that these masks are not equivalent to N95 masks but are to prevent transmission in addition to distancing and sanitation.
I’m getting my sewing machine out this afternoon. I have some bug fabric that seems appropriate!