That rule, from the California Occupational Safety and Health Standards Board, would have allowed workers in nearly all settings to forgo masks only in circumstances where everyone in a room had been vaccinated against COVID-19. If just one person was not vaccinated, everyone would have been required to wear a mask.
That contrasted with the state's broader plan to do away with virtually all masking and social distancing requirements for vaccinated people, which more aligns with the latest recommendations from the U.S. Centers for Disease Control and Prevention.
The board initially rejected the mask place regulation before giving it the go-ahead in early June – a decision that prompted anger from business advocacy groups that said it would place an undue burden on employers.
Wednesday night's board meeting was attended by members of the public, workers, industry leaders, and employers who voiced their complaints during more than two hours of public comment.
The safety board's staff was not specific on what changes it will recommend at its scheduled meeting next week, other than it will try to conform more closely with public health guidelines.
Helen Cleary, director of the Phylmar Regulatory Roundtable, said the back-and-forth on state workplace regulations has created an atmosphere of confusion.
"Employers cannot plan with this high level of uncertainty," she said in a statement. "We are disappointed and frustrated with the confusion, the process, the substance and the lack of leadership."
A dozen business groups and organizations representing manufacturers, farmers, tourism interests and other industries sent a letter to Newsom asking him to rescind the board's regulations ahead of Wednesday night's reversal.
Requiring masks unless all are vaccinated in a workplace would "create yet another barrier to rehiring and reopening" at a time when "we need to be providing incentives to bring people back," they said.
The board's controversial workplace decision comes as Democratic Gov. Gavin Newsom faces a likely recall election, brought about by discontent over his handling of the pandemic.
Michael Miller, California Association of Winegrape Growers government relations director, told board members before the vote that the general public "doesn't draw a distinction between this board and the rest of the Newsom administration."
"What they hear is the Newsom administration say that wearing masks at work may be here to stay," he said.
Business groups also want the board to withdraw its proposal to require employers to start providing the most effective N95 masks for voluntary use by employees who work indoors or at large outdoor events and are not fully vaccinated, starting July 31. They said that would be costly and compete with the needs of health care workers.
Board members emphasized prior to Wednesday’s vote that their revised rules were temporary. The board's decision to withdraw the workplace rule before it was supposed to go into effect allows the board to consider changes at a meeting next Thursday and potentially implement those changes before the end of the month.
The Associated Press contributed to this report.