Vaccination or frequent testing had been a requirement for workers in settings with a high-risk of viral transmission since last summer.

BART reversed itself to reinstate masks, even though the California Department of Public Health also announced last week that it would align with the CDC and drop its own mask requirement for public transit and transit hubs like bus stations and airports.

The county's seven-day average of new Covid cases has held below 550 for six consecutive days. 

Local jurisdictions are free to impose their own requirements, but all students and staff, regardless of vaccination status, will no longer be required by California to wear a mask indoors at schools and child care facilities starting March 12. 

Contra Costa, Marin, San Francisco, Alameda, and Sonoma counties said their rules won't change, despite the month long statewide mandate that went into effect Wednesday morning.  

Mayor Sam Liccardo said the mandate will reduce risk of “super spreader” events at major city venues.