COVID-19: US CDC are recommending homemade masks, if none other are available
In settings where N95 respirators are so limited that routinely practiced standards of care for wearing N95 respirators and equivalent or higher level of protection respirators are no longer possible, and surgical masks are not available, as a last resort, it may be necessary for HCP to use masks that have never been evaluated or approved by NIOSH or homemade masks. It may be considered to use these masks for care of patients with COVID-19, tuberculosis, measles, and varicella. However, caution should be exercised when considering this option.
https://www.cdc.gov/coronavirus/2019-ncov/hcp/respirators-strategy/crisis-alternate-strategies.html
See also:
- https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/face-masks.html
- https://www.osha.gov/video/respiratory_protection/resptypes_transcript.html
(I'm evaluating specific mask designs, will follow up.)