San Mateo County residents 65 years and older line up for a COVID-19 mass vaccination clinic at the San Francisco International Airport on Friday, Feb. 12, 2021. (Photos courtesy of San Mateo County Health)

San Francisco, Santa Clara and Marin counties moved into the state’s orange tier of COVID-19 restrictions Tuesday, allowing them to expand indoor capacities for some businesses and reopen bars outdoors.

The three counties join San Mateo County as the only Bay Area counties to proceed into the orange tier since the state’s stay-at-home order was lifted in January.

The tier change from red to orange will allow each county to increase indoor capacity from 25 percent to 50 percent for sectors like places of worship, movie theaters and restaurants while gyms and fitness centers will be allowed to raise capacity from 10 percent to 25 percent.

Orange is the most restrictive tier in which bars can operate under any circumstance. A move to the yellow tier allows a county to resume indoor operations at bars at 25 percent capacity or 100 people, whichever is fewer, according to the California Department of Public Health.

In addition, business sectors like family entertainment centers, cardrooms, offices and wineries will be allowed to resume indoor operations after being limited to opening outdoors or being closed altogether in the red and purple tiers.

Santa Clara County Health Officer and Public Health Director Dr. Sara Cody said the tier change reflects the county’s persistence in reducing its cases and hospitalizations but advised residents to continue observing the public health guidance that has become rote over the last year.

“To continue to prevent cases and resultant hospitalizations and deaths, we must continue to wear masks, social distance, stay outdoors as much as possible, and get vaccinated when it’s our turn,” Cody said. “We are close to a significant increase in vaccine supplies, but until those doses are in arms, we must protect each other against another surge.”

On April 1, counties in the orange tier can allow 33 percent capacity crowds at outdoor professional sporting events and 25 percent capacity or 500 people, whichever is fewer, at amusement parks.

Guests at outdoor arenas must be state residents while amusement park guests must live in the same county as the venue.

The three counties will be required to remain in the orange tier for at least three weeks before they are eligible to move to the yellow tier, the least restrictive section of the state’s reopening system.

Marin County Public Health Officer Dr. Matt Willis said the coming weeks will be “pivotal” for the county.

“We saw an uptick in cases last week and with variant cases increasing, we don’t want to drop the ball before we reach the goal line,” Willis said. “Letting your guard down puts us at risk of slipping backward. While pandemic fatigue is real, we must stay the course to help Marin reach (the yellow tier).”

Details on which businesses can operate in the orange tier and at what capacity can be found at https://covid19.ca.gov/safer-economy.