Companies with financial stakes in the ongoing negotiations between the United Steelworkers and Shell Oil Co. aren't the only ones keeping an eye on what's happening at the bargaining table.

Plenty of companies that don't have union-represented employees are paying attention to the labor negotiations that affect the livelihood of 30,000 workers at the nation's refineries, chemical plants, pipelines and oil terminals, including 5,000 in the Houston area.

The union went on strike Sunday at nine refineries and chemical plants, including five in the area, after talks broke down with Shell, which is representing the oil industry. On Wednesday night, the union received a new offer and is considering it. Details were not disclosed.

If this year is like other years, employees at nonunion companies will likely get the same raises - or maybe even a more attractive pay package - than those at union-represented companies. Companies with both union and nonunion facilities tend to want to pay as well or better at nonunion-represented plants so the workers will continue to remain union-free, said Bill Bux, a lawyer with Locke Lord who specializes in the management side of labor relations for management clients.

"Or else they'll become unionized," he said.

Many companies prefer that their employees not be represented by labor unions because they believe it keeps production costs down and provides more flexibility, Bux said.

Without a union, they don't have to deal with a seniority system and they don't have to wrangle with union rules that prohibit one craft from doing the work of another craft, he said.

It's not just energy companies that match union-negotiated compensation packages, said Julius Getman, a law professor emeritus at the University of Texas.

Getman, author of "Restoring the Power of Unions: It Takes a Movement," recalled a big Las Vegas casino owner who was bitterly anti-union but paid the prevailing union wage. He said the owner did so because he was competing for the same pool of employees who could find jobs at other casinos that were represented by labor unions.

Sometimes the competitive pressure extends to benefits, Getman said, recalling a conversation he had with the owner of a Midwestern manufacturing company who told him that if he wants to stay nonunion, he simply pays what the union gets in its labor agreements.

One local labor leader said it doesn't bother him that nonunion employees are getting some of the same benefits as their union counterparts.

"I'd wish they'd join," said Lee Medley, president of the United Steelworkers Local 13-1. "We'd be stronger together."

One thing that does annoy him, however, is that many folks think unions are just about negotiating wage packages. It's a whole lot more than that, he said, ticking off the job protections unions provide, such as being able to point out unsafe working conditions without fear of being fired for speaking up.

Competitive wage pressure is especially strong in industries in which there are a lot of organized workers and high demand for skilled labor.

To keep some competitors from stealing their workers, some industrial construction companies are adding what's known as a "per diem" fee to employee wages.

In some cases, this fee of $100 to $150 a day to cover transportation, lodging, food and other expenses works out to be more than the union-negotiated hourly wage, said Michael Cunningham, executive director of the Texas Building and Construction Trades Council. Some companies have gotten into trouble lately with the U.S. Department of Labor for not including the per diem fee when calculating overtime pay.

"This is an employee's market now," said Cunningham, who said demand for skilled construction workers is especially strong at refineries, power plants, chemical plants, LNG processing plants, and gas and oil terminals.