California: Masking for All Indoor Public Settings Required as of December 15

December 14, 2021

The California Department of Public Health on December 13 announced that it will require all people—regardless of COVID-19 vaccination status—to wear face masks in all “indoor public settings” from December 15 through at least January 15, 2022, noting that increased infection and hospitalization rates have triggered this new requirement. Since Thanksgiving, the statewide seven-day average case rate has increased 47%, and hospitalizations have increased 14%.

At the time of publication, neither the California Department of Public Health (CDPH) nor the governor had issued a new order requiring masking. Instead, the CDPH updated its guidance (hereafter “updated guidance”). The updated guidance does not define “indoor public setting.”

The state’s previous information on masks had required only unvaccinated people to mask while visiting indoor “public places,” and had provided examples of such places, including retail stores, restaurants, theaters, family entertainment centers, meetings, or government offices that serve the public. The  FAQs include indoor local board and commission meetings open to the public as examples of “indoor public settings.” Under the updated guidance, all people—even if fully vaccinated—must mask when visiting at least these locations starting December 15.


The updated guidance includes exemptions for individuals with medical or mental health conditions, or disabilities that prevent mask-wearing, including individuals who are hearing impaired. The updated guidance also exempts people who would create a risk to themselves by wearing a face covering in the course of their work, as determined by local, state, or federal regulations or workplace safety guidelines.

New Travel Advisory with COVID-19 Testing Recommendation

The CDPH also issued a new travel advisory, which most significantly advises that “all travelers arriving in or returning to California from other states or countries should test 3–5 days upon arrival.”

The new travel advisory also notes that travelers arriving in or returning to California should follow Centers for Disease Control and Prevention (CDC) travel guidance and that all travelers arriving in or returning to California who test positive or develop COVID-19 symptoms should isolate and follow public health recommendations.

‘Mega Event’ Attendance—Updated Requirements for the Unvaccinated

The CDPH also updated its guidance on testing requirements for unvaccinated individuals attending indoor “Mega Events” (more than 1,000 attendees). Current rules require testing within 72 hours of the event absent proof of full vaccination.

Effective December 15, people attending indoor Mega Events who are unable to provide proof of full COVID-19 vaccination status must undergo a COVID-19 test within one day for antigen tests, and within two days for polymerase chain reaction (PCR) tests, prior to entering the facility or venue.

The shorter time periods for testing also are recommended for outdoor Mega Events (10,000 or more attendees).

Implications for Employers

The CDPH’s updated guidance is the latest in fluctuating face mask and other COVID-related requirements for businesses in California—although roughly half of California’s population lives in counties that already have indoor face mask mandates in place regardless of vaccination status. Several of those local indoor face mask mandates, such as in Los Angeles County and Santa Clara and San Mateo counties in the Bay Area, expressly include private offices.

Employers should consult with counsel and continue to monitor requirements in their locations.

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If you have any questions or would like more information on the issues discussed in this LawFlash, please contact any of the following Morgan Lewis lawyers:

Los Angeles/Century City
Jacqueline C. Aguilera
Kathryn T. McGuigan
Jason S. Mills

Orange County
Daryl S. Landy

Silicon Valley/SF
Alicia J. Farquhar