In a move criticized by business groups and hailed by labor advocates, California’s workplace regulators extended the state’s coronavirus pandemic regulations into next year with revisions that employers said could worsen the state’s severe labor shortage.

The revised rules require that vaccinated but asymptomatic workers who come in close contact with someone infected with the virus must wear masks and stay 6 feet from others for 14 days if they return to work.

The current rules allow those employees to keep working without restrictions unless they show symptoms _ under the assumption that the vaccine generally will protect them.

An unvaccinated worker who comes in close contact with someone infected with the virus still must quarantine for two weeks.

The new rules that take effect Jan. 14 for three months in the most populous state were approved by the California Occupational Safety and Health Standards Board. The seven-member safety board is the policy-making arm of what is known as Cal/OSHA. It adopted the revised rules without discussion on a 6-1 vote.

Business groups argued the new rules will be particularly onerous for small businesses including restaurants and retailers.

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