This is probably county base because the SF and Alameda county which includes Oakland and Fremont have already lifted the mask mandate for healthcare facility for their patients but healthcare workers still needs to mask up.
However, Santa clara county has not lifted anything for health care facility.
If anything, I noticed that asian folks are still masking up more in the bay area. If I ever go to their asian grocery stores, you will see over 60% of the asian people in there are all masking up. Now to get an idea of the general population, just go to walmart and do a mask head count.