STOCKTON — Citing 100 percent participation, 320 union workers at Simpson Strong-Tie hit the sidewalks around the plant in the city’s airport industrial park last Thursday and were still at it Tuesday, equipped with horns, sensible shoes and picket signs citing their employer as unfair and calling for a fair labor contract.

It’s the first strike at the gigantic, 800,000-square-foot manufacturing plant since 2007, when about 270 workers stayed out on strike for a little over a week. At that time, the issues were the same as they are today: pensions, health care benefits and wages.

A top Simpson manager said Tuesday that the contract presented to SMART Local Union 104 last Thursday was “a reasonable package very commensurate with other businesses in the area. We value all our employees. We do provide fair wages and benefits.”

That contract proposal was overwhelmingly rejected by union members in a vote on Saturday.

Simpson Stockton branch manager Bruce Lewis, who has been with the international company since 1994 and in Stockton since the plant first opened here about 16 years ago, kept details of the contract offer private, saying it would be inappropriate to negotiate through the media.

“Negotiations are a normal part of the labor relations process. We’re hoping to find a mutually beneficial solution and come to agreement soon,” Lewis said, adding: “We are planning to meet later on this week.”

Matt Richard, business representative for Local 104 of SMART — an acronym for Sheet Metal, Air, Rail, Transportation — said Tuesday the union members “are seeking to keep their health care coverage intact, a dime into their pension and a raise that lets them keep up with the rise in rent, food, gas and other items needed to support working families.”

The workers say they are attracted to Simpson not because it pays the highest wages but because of its pension and health care benefits. The company said it currently pays 100 percent of employee health premiums but is asking employees to share a portion of that expense in the future.

Employees currently are covered by Blue Shield health insurance, but the contract proposal calls for Kaiser Permanente to be the new provider.

“They want to switch us to Kaiser, but the wage increase they are offering will be consumed by the switch,” said union member Davis Phioumavong, 36.

Juan Macias, 53, a 23-year veteran with Simpson who started with the company in San Leandro before it moved the plant to Stockton, makes $18.95 an hour. He said new employees start between $14 and $16 an hour and the company “doesn’t want to pay more than $21.”

In the process of fabricating standard metal parts for the building and construction industries, Macias said “there are lots of injuries — cuts, bad backs, shoulders — and the company doesn’t do a good job with that.”

One older employee on Tuesday’s picket line outside the plant at 5151 S. Airport Way, who declined to provide his name, said: “Nobody here wants to go on strike. We’re ready to go back in a heartbeat as long as it’s a fair contract, but we’re out here for a reason to get our point across. We’re not here to break the bank. We’re all together here for a fair contract.”

Contact reporter Joe Goldeen at (209) 546-8278 or jgoldeen@recordnet.com. Follow him on Twitter @JoeGoldeen.