About 90 percent of the roughly 90 workers at the de Young and Legion of Honor museums voted to give their union, Service Employees International Union Local 1021, the power to call a strike, union spokesman Carlos Rivera said. The vote took place over three days last week.
The workers transport, catalogue, secure and display the pieces and exhibits at the two museums, which are run by the nonprofit Fine Art Museums of San Francisco.
Rivera said negotiations have been taking place over the past nine months with museum management.
"They're siphoning that money into lawyers' pockets versus coming to a settlement agreement," he said.
SEIU Local 1021 is opposing proposals to pay new employees less, eliminate seniority increases for recently hired workers and increase health care costs, according to the union. The previous contract expired at the end of July.
"They're cracking down and trying to make sure museum workers sell out future museum workers," he said.
Ken Garcia, spokesman for the Fine Arts Museums of San Francisco, defended the proposal to the union.
"It's unfortunate that the union's leadership has taken this step in light of what the museum considers an extremely fair and generous contract offer," Garcia said.
"We think it's quite remarkable that this union, or for that matter, any union, would choose to walk away from a double-digit pay raise in these harsh and difficult economic times," he said.