The ordinance, passed by the Los Angeles County Board of Supervisors, makes face coverings mandatory for workers at grocery stores, pharmacies, food delivery platforms and other essential businesses.
Under the new guidelines, businesses must either provide employees with non-medical grade cloth face coverings, gloves and hand sanitizer or give workers money to buy these items. Employees, in turn, must wear face coverings and gloves while at work.
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Businesses must also display information on a physical distancing protocol, explaining to the public how safety requirements are being met.
Shoppers must also put on a facial covering, including scarves and bandanas, while in an essential business. The measure allows grocery and drug stores to refuse service to any customer not wearing a face mask. Those who do not comply to the mandate risk being fined.
In addition to brick-and-mortar grocery stores that remain open, many people following stay-at-home orders have turned to online food delivery services. The ordinance also covers shoppers and delivery people for companies like Instacart, DoorDash and Shipt.
California's local governments have been the front-line responders to the crisis. Some, like Los Angeles and the San Francisco Bay Area counties, have taken more aggressive approaches than called for in Newsom's stay-at-home order, in some cases requiring the public to wear face masks.
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California has been under an open-ended, statewide stay-at-home order since March 19. However, the virus' spread has been uneven, with even some highly populated areas reporting remarkably low totals and some rural counties reporting only a handful of cases and some with none at all.
During a press conference on Tuesday, Gov. Gavin Newsom announced a detailed plan for modifying California's statewide coronavirus restrictions, a decision he said he made without "political pressure," an apparent reference to President Donald Trump declaring himself the ultimate decision-maker for when states can reopen.
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Los Angeles County, the state's largest with 10 million residents has 40% of the cases and nearly half the deaths.
Following Newsom's announcement Tuesday, Assembly Speaker Anthony Rendon, a Los Angeles-area Democrat, said the state "must take steps that are at once decisive and responsive to the changing conditions of the COVID crisis."
"That's what today's guidelines represent," he said.
For ABC7's complete coverage of the coronavirus pandemic, visit abc7.com/coronavirus.
The Associated Press contributed to this report.