While Marin County remained in orange, San Francisco became the first Bay Area county to advance to the least-stringent yellow tier based on the update on tier levels by the California Department of Public Health.

The jump into the yellow tier means that San Francisco would be able to move forward with new reopenings and expand additional activities. The city said that its new public health order would align with the state, but only with some exceptions.

According to SF Gate, the county's Health Director Matt Willis encouraged residents in the area to follow the new guidelines. He added that he knows that some citizens are disappointed by the measures imposed, but he emphasized the importance of understanding the purpose of the actions in the first place.

The state made its announcements on new tier assignments on Tuesdays, and counties can move forward with reopenings as early as Wednesday. 

But counties can move at a slower pace compared to the state. San Francisco will be allowing the new reopenings to start on May 6.

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Reopenings and Limitations

The San Francisco reopenings on Thursday include indoor bars, wineries, and breweries but only 25 percent capacity and a limit to only 100 people. 

The previous limit of the three-household table on indoor dining improved as they will allow up to eight individuals per table.

Eating or drinking in cafes or restaurants in grocery and other retail stores will be allowed as long as customers and owners follow indoor dining rules set on the guidelines.

For sports enthusiasts, ice-skating and roller-skating rinks, arcades, golf, and playgrounds can open at up to 50 percent capacity. Even mini-golf, pool halls, and bowling alley owners can also expand their capacity up to 50 percent.

Also, small outdoor gatherings can expand to 75 participants, even if food and beverages are consumed. Masks will be allowed to be removed as long as the required social distancing of six feet will be maintained between attendees. However, individuals who were not able to get inoculated are encouraged to wear facial coverings, San Francisco Chronicle reported.

For small indoor gatherings, 50 percent capacity is also allowed for a maximum of 50 individuals with face masks required. But everyone can remove their face coverings once each one is fully vaccinated, or there's only one unvaccinated household that is also low-risk.

For offices and libraries, they will be allowed to expand to 50 percent capacity, even without counting the fully vaccinated personnel.

Venues for an indoor live audience may expand to 50 percent capacity. However, those events in which food and beverages are served may host groups of less than 200 individuals without requiring proof of vaccinations or negative test results. 

Events up to 300 people that are taking up less than 25 percent of the venue capacity do not require approved health and safety plan or proof of vaccination, or negative test results of COVID-19.

Outdoor live audience venues may expand to two-thirds or 67 percent capacity in events where food and beverages are served up to a maximum of 300 individuals, without a requirement of presenting proof of vaccinations. While outdoor arts, music, and theater festivals are permitted to expand to 100 individuals' capacity.

About 50 percent capacity is also allowed for indoor fitness and athletic recreation youth and adult facilities, while classes may also expand to 50 percent but with a limit of 200 people.

The same thing will be observed in indoor swimming pools. But for saunas, steam rooms, and indoor hot tubs, businesses may reopen but only at 25 percent capacity. 

Adult day programs and senior community centers can also expand to 50 percent indoor capacity, but only up to 50 people.

ABC7 reported that San Francisco's test positivity rate was at 0.6 percent and its average rate of new COVID-19 cases was 1.8 per 100,000 residents from April 18 to April 24. These low numbers allow the county to join the state's least restrictive tier.

The report added that around 72 percent of San Franciscans over 16 received at least one dose of the vaccine, and about 49 percent were already fully vaccinated.

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 WATCH: San Francisco Enters Yellow Tier Thursday - From NBC Bay Area