OAKLAND  (AP) — Bay Area Rapid Transit's two largest unions voted Friday on a tentative contract agreement after a bitter labor dispute prompted two strikes.

More than 2,300 members of Service Employees International Union Local 1021 and Amalgamated Transit Union Local 1555 voted on whether to approve a new four-year contract that includes a 15 percent raise and improved safety conditions.

The agreement also requires BART workers to pay into their pensions for the first time and increases their monthly health care contributions from about $92 to $129. The unions represent train operators, station agents, custodians and maintenance and clerical workers.

The vote also comes nearly two weeks after the unions reached a deal with BART management that ended months of tortured talks over salary, benefits and safety conditions. The unions went on strike for nearly five days in July and after a state-mandated cooling off-period, went back to the picket lines for another four days last month angering thousands of commuters.

During the second strike, two BART workers killed by a train operated by an employee under training in Walnut Creek on Oct. 19 which many believe drew the parties back to the bargaining table to finally iron out a deal a couple of days later.

SEIU said they will announce its voting results late Friday.

"We've already gotten an amazing turnout. We've had members waiting in line getting ready to vote early this morning," SEIU spokeswoman Cecille Isidro said. "We're optimistic they will approve it."

ATU President Antonette Bryant shared a similar view Friday.

"I think the members will come down and make their choice," Bryant said. "Our executive board is recommending a yes vote, but it remains to see what the members' choices are."

If the two unions ratify the contract, BART's board of directors would likely then vote on the new contract during a special meeting, BART officials have said.