A limited loosening of COVID-19 mask mandates goes into effect Friday in San Francisco and Marin County, with Contra Costa County joining them Nov. 1.
A wider lifting of mask restrictions in most Bay Area counties is further off — though Marin is on track to meet the required coronavirus benchmarks soonest.
Here’s what you need to know about what has changed in Bay Area mask mandates, and what changes are expected down the line.
What’s changing now
Starting Friday, people fully vaccinated for COVID-19 no longer need to wear a mask in some indoor settings in San Francisco and Marin County where the same fully vaccinated group gathers.
That includes offices, gyms and fitness centers, employee commuter vehicles, religious gatherings, and indoor college classes not exceeding 100 people. Operators of such spaces can still choose to impose their own face covering restrictions, according to health officials.
San Francisco and Marin County will still require indoor masking in places for the general public (think restaurants and retailers). Masks can come off if actively eating or drinking. Lifting mask rules at those venues will take longer, in accordance with the criteria spelled out by officials in the broader Bay Area.
Who is affected now
Fully vaccinated people can take their masks off in those limited “stable cohort” settings in San Francisco and Marin County, where fully vaccinated people gather. Unvaccinated or partially vaccinated people (just one dose of Pfizer or Moderna) still must wear masks indoors under state guidelines.
What has been the response from major employers?
One hope for the lifting of the mask mandate for vaccinated offices is that more people will return to work, thus helping to revitalize downtown areas. While generally cheering the mask move in San Francisco and Marin, Rufus Jeffris, spokesperson for the Bay Area Council, said most employers likely will move cautiously on their return-to-office plans.
Facebook and Google, two of the Bay Area’s largest employers, both of which belong to the Bay Area Council, say their existing mask policies will not change for now.
What rules are still in place?
In San Francisco and Marin, all people must continue to wear masks in indoor public settings where the population that frequents the business or institution changes. Think restaurants and retailers.
In Alameda, Contra Costa, Napa, San Mateo, Santa Clara and Sonoma counties, nothing has changed yet. Indoor masking is still required by everyone age 2 and older in all public spaces, regardless of vaccination status — with exceptions for those with certain medical conditions, disabilities and hearing impairment.
Solano County did not issue a mask mandate for vaccinated people. The cities of Benicia and Vallejo have enacted their own universal mask mandates, in line with the other Bay Area counties — those rules apply only within city limits.
Under federal and state rules, masks are required in California for people on planes, trains, buses, ferries, taxis, ride shares and other forms of public transport, transportation hubs, health care settings, state and local correctional facilities and detention centers, shelters and cooling centers, and indoors in facilities for youths, such as K-12 schools, child care centers and day camps.
What happens next?
Contra Costa County will join San Francisco and Marin in the limited lifting of mask requirements on Nov. 1.
But the Bay Area has also instituted guidelines for broadly removing the face covering requirement. Each jurisdiction must meet three criteria:
• Low community transmission as defined by the Centers for Disease Control and Prevention. Case rates must be in the yellow/moderate tier for three consecutive weeks.
• Low hospitalization rates, which are defined by county health officers.
• At least 80 percent of the total population must be fully vaccinated, or if the county does not meet that threshold, there must be a vaccine available for emergency use to children ages 5 to 11 for at least eight weeks.
Which counties are close to fully getting rid of their indoor mask mandates?
Marin County is the closest to meeting the regional requirements to broadly lift its mask rules for fully vaccinated people.
Marin is the only Bay Area county so far to hit the key 80% vaccination benchmark. Other Bay Area counties, where vaccination rates vary from about 66% to 75%, do not expect to hit that goal for several months.
Marin also was in the CDC’s “moderate” transmission county this week, and if it remains there for three weeks, it will almost certainly meet the criteria.
Seven of the nine other Bay Area counties remain in the “substantial” transmission category, labeled orange on the map. Napa County is the lone holdout in the region stuck in the worst “high” transmission category, which is red.
How safe is it to remove your mask where it’s now allowed?
Infectious diseases experts are split on whether it’s safe to remove a mask in an indoor setting. On one hand, gym-goers exhale heavily, and office workers may sit in close proximity to one another. As the weather cools, people are more likely to huddle up for warmth and celebrate the holidays inside.
On the other hand, if a space was well-ventilated and people were vigorous about testing and staying home if they felt ill, it could be safe to be inside. Experts told The Chronicle that immunocompromised and older people who haven’t yet received a booster shot should assess their own sense of risk and wear a mask inside if they’re more comfortable with that.
Gwendolyn Wu is a San Francisco Chronicle staff writer. Email: gwendolyn.wu@sfchronicle.com