Some San Francisco retailers, bars requiring masks, vaccination proof

Some San Francisco retailers on Thursday will start requiring customers to wear masks and proof of vaccination to enter their business. 

At the Apple store in Union Square, a guard said that anyone who enters the building must mask up regardless of their vaccination status. 

The Cupertino-based company says about half of its 270 retail stores in the United States require customers to mask up if they head indoors.

New requirements will apply mostly to stores that are in places seeing a high number of cases of COVID-19, like Los Angeles and Chicago. 

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But stores in other places, like the Bay Area, can opt-in to the policy, too. 

The company says it is strongly encouraging - but not requiring - its workers to be vaccinated.

The Apple policy comes just two days after the CDC changed its guidance, advising even vaccinated people to wear masks in indoor settings.

Also taking effect on Thursday, a new mandate from the San Francisco Bar Alliance representing about 500 bars. 

Some of them will require their customers show proof of vaccination or bring a copy of a negative COVID test with them.

It's up to each individual bar to decide whether to enact the policy.

"Every single unvaccinated person who does not hang out indoors, in San Francisco is a win for us," said the alliance's founder, Ben Bleiman. "Right now. We know they are much much more likely to spread the virus."

Bleiman said they decided to enact the policy after some of their fully vaccinated staff  got infected.