A strike by the Sprinkler Fitters Union Local 699 this week is shutting down construction sites around the Puget Sound area, including Franciscan’s St. Anthony Hospital in Gig Harbor.

The union, which represents workers who install fire protection sprinkler systems in commercial buildings, went on strike at midnight Tuesday after the workers and the companies that employ them couldn’t agree on a new contract.

Workers picketed Wednesday outside construction sites – such as the new Nordstrom at the Tacoma Mall and St. Anthony – where they would be working if they had a contract.

Members of other labor unions have also stopped working in support of the strike, shutting down building sites in Western Washington.

The union and the companies that employ its members – represented by the local office of the National Fire Sprinklers Association – have been negotiating over a pay increase and contract language, said Gordon Sansaver, who is on the contract negotiating committee and the union’s executive board.

“We are one of the hardest-working crafts in any industry. We are proud of that,” he said.

The employers – a group of construction and sprinkler companies – offered a $14-an-hour increase over four years, said Jeff Bennett who is with the Seattle-based McKinstry Co. construction company and a member of the bargaining team. Other details of the proposed agreement weren’t disclosed.

Bennett said the union members have among the best benefits around and are paid well.

A full-time union member can make $100,000 a year, he said. But union members say that includes overtime work.

Bennet said the employers made their final offer on Monday, which was rejected by the union. They are waiting for the union to call for further negotiations.

The union represents more than 500 workers in seven Western Washington counties including Pierce and King.