Workers with the Hudson Valley office cleaners union from White Plains and local cleaning contractors managed to stave off a strike by reaching a tentative contract last night, a union official said.

The group was seeking higher wages, health benefits and family benefits for union members in the Hudson Valley and the Fairfield, Conn., region.

A few hundred members of Local 32BJ voted yesterday afternoon to authorize a strike - slated for Jan. 1, when the current contract runs out - since the parties had yet to reach a new contract.

However, by 9 p.m. the parties reached an agreement and were busy working out the details, said Shirley Aldebol, Hudson Valley director of Local 32BJ.

"This is a huge victory for the workers," she said of the agreement, which affects 4,500 workers in the Hudson Valley and Connecticut. "... It is historic for this market."

Under the new contract, employees will see a 19 percent pay increase over the next four years, which amounts to a $2 increase in base pay, Aldebol said. By 2012, the base pay will be $12.50 per hour.

The contract also allows enhanced benefits for part-time workers. Under the old contract, part-timers had no benefits. Now, Aldebol said, they will have vision, dental, prescription and life insurance coverage.

Cleaners who work in buildings larger than 400,000 square feet in White Plains, Stamford, Conn., and a few other buildings in Connecticut will receive family health care coverage under the new contract.

The four-year contract will take effect Jan. 1.

Had the workers gone on strike, their absence would have affected more than 125 buildings in White Plains, Yonkers, New Rochelle and other parts of the Hudson Valley, according to a news release issued by the local.