The counties of Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Sonoma and the City of Berkeley will lift the indoor masking requirement in public spaces not subject to state and federal masking rules when all the following occur:

• The jurisdiction reaches the moderate (yellow) COVID-19 transmission tier, as defined by the Centers for Disease Control & Prevention (CDC), and remains there for at least three weeks
• COVID-19 hospitalizations in the jurisdiction are low and stable, in the judgment of the health officer
• 80% of the jurisdiction’s total population is fully vaccinated with two doses of Pfizer or Moderna or one dose of Johnson & Johnson (booster doses not considered)
• OR Eight weeks have passed since a COVID-19 vaccine has been authorized for emergency use by federal and state authorities for 5- to 11-year-olds

Why is there an eight week window?

“Because it will take at least that long for kids to start getting their two doses, they are three weeks apart, and you need another week or so to be fully immune,” said Dr. Yvonne Maldonado, a Stanford Professor of Pediatrics and Infectious Disease Physician.

Bay Area residents react to possibility of mask guidelines being eased

Cody says the metrics were designed to be simple but thorough.

“Essentially we want to ensure that we have many layers of prevention, we want to make sure that the vaccination layer is really robust before we peel back the masking layer,” Cody said.

Santa Clara County is currently in the CDC’s orange tier, but transmission is trending down.

RELATED: Los Angeles passes one of the strictest COVID vaccine mandates in the US

“I think it’s going to be hard to say when we will meet all three metrics,” said Cody.

Cody says the most important metric to meet will be the vaccination requirement – adding some counties will get there faster.

“We are seeing 900 to 1,000 new first dose vaccinations across the county every single day,” said Contra Costa Health Officer Dr. Chris Farnitano.

Farnitano says if that pace keeps up, the county could reach the 80 percent mark within two to three months.

“We may be looking at December or maybe even January depending on the timing of the FDA authorization,” he said.

RELATED: Solano Co. defends past decision to keep businesses open

All Bay Area counties and the city of Berkeley have adopted these guidelines with the exception of Solano County. Health Officer Dr. Bela Matyas says he stands by his decision not to implement an indoor mask mandate.

“None of the counties that had such a mask mandate showed any benefit,” Matyas said. “All of them should have seen a reduction in disease within at most two weeks, none of them did.”

So far no Bay Area county meets the qualifications for all three metrics. Health officers say even if mandates are lifted, it won’t prevent individual businesses from imposing their own restrictions.

RELATED: SF General Hospital says 115 staff members are off schedule pending vaccine status

Separately from the other Bay Area jurisdictions, SF announced a more immediate easing of masking requirements beginning on October 15 in certain, select indoor settings where stable groups of fully vaccinated people gather. These settings include offices, gyms, and fitness centers, employee commuter vehicles, religious gatherings, and indoor college classes or other organized gatherings of individuals who meet regularly, not exceeding 100 people.

Currently every Bay Area county is in the orange tier, which means no county is eligible to ease the restrictions for three weeks.

Lifting a local indoor mask mandate would not prevent businesses, nonprofits, churches or others with public indoor spaces from imposing their own requirements.

VACCINE TRACKER: How California is doing, when you can get a coronavirus vaccine

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