If there were any doubt that health care was big business in the Lehigh Valley, a look at 2002's largest employers makes it clear.

Six of the top 25 largest companies are directly involved in health care, according to data compiled by The Morning Call. They include two of the top three employers, Lehigh Valley Hospital and Health Network, and St. Luke's Hospital and Health Network. Three other hospitals and national nursing home company HCR Manorcare also made the list.

Other 25-largest employers involved in health care include B. Braun Medical medical supplies and Aetna health insurance.

The dominance of health care on the local labor market is a trend that will continue as people live longer and baby boomers reach the age when they require more medical treatment, said Robert Zimmel, senior vice president of human resources for St. Luke's.

''It's a growing industry, and with the change in demographics the need for health care is going to increase,'' he said. ''We're hiring at a rapid pace. The economy has not had an effect on us.''

The Lehigh Valley 25 largest companies list measures employment in Lehigh and Northampton counties only. So, for example, employment at Agere Systems' plant in Reading is excluded. The list also excludes government agencies and public school districts.

Of course, a list of large employers doesn't mean what it once did. The Lehigh Valley labor market used to be dominated by large factories, but today, 43 percent of local employees work for companies with fewer than 100 workers. And about 25,000 people, almost 10 percent, work for companies with fewer than 10 employees, according to data kept by the Lehigh Valley Economic Development Corp.

But among the largest workplaces, health care dominates.

''We certainly feel that it's an honor to be the largest employer because that's also important for the economy of the area when employers are able to provide jobs,'' said Brian Downs, spokesman for Lehigh Valley Hospital. ''This is not something we planned. The community is entitled to the highest quality health care, and it's our mission to provide that care.''

LVH, as it's known, has reduced its operating costs by $100 million over the past eight years, without major layoffs, Downs said.

''Our work force has grown to meet the community's growing demand for our services.''

St. Luke's would actually move to No. 2 on the list if its other nearby facilities were added, including St. Luke's Quakertown Hospital. That would boost its employment to more than 5,000.

All local health care providers are likely to continue boosting their payrolls, especially for such jobs as nurses, pharmacists and radiology technicians, Zimmel said. ''It's hard to find good people, because the supply and demand don't quite match up at this point,'' he said.

The local hospitals are non-profit, except for Easton Hospital, which since mid-2001 has been owned by the for-profit Community Health Systems of Tennessee.

The largest for-profit company in the Top 25 is Air Products and Chemicals. At No. 2 overall, it employs more than 4,200 at its huge campus off Route 222 in Trexlertown. And that's not including its Hometown plant in Schuylkill County.

''Emerging as the largest for-profit employer in the Lehigh Valley is actually quite a heavy responsibility,'' said Leonard Broese van Groenou, Air Products' vice president of human resources. ''Although we are an international company operating in 30 countries around the world, we are headquartered here and are very conscious of the effect we have on this community.

''Air Products' success is closely linked with the success of the Lehigh Valley.''

He said Air Products' employment in the Lehigh Valley has been about the same for the past 20 years.

''Our business mix and the leadership positions we hold in many markets around the world have given us reasonable stability over the years,'' he said.

No. 4 company Agere Systems, the Allentown-based spinoff from Lucent Technologies, has had an interesting employment history in recent years. During the late 1990s and 2000, it couldn't hire workers fast enough, as the telecommunications industry boomed and demand soared for its semiconductors and fiber-optic system parts.

But over the past two years, it has been weathering a meltdown in the telecom business, and its employment has tanked.

In 2000, it employed more than 6,000 at its Allentown area facilities. Today, that number is 3,725. And with a phase-out of its local manufacturing, 1,500 more already-announced layoffs are yet to come. Its target employment figure is 2,300 locally.

PPL, the Allentown power company and owner of the lone skyscraper that dominates the city skyline, ranked No. 3 among the profit-making companies and fifth overall.

The Top 25 list contains mostly companies based in the Lehigh Valley, but maybe one surprising out-of-town employer ranks No. 6: Giant Food Stores, which employs 2,038 workers locally.

Giant, of Carlisle, Cumberland County, is a huge employer across Pennsylvania, ranking as the state's third-largest private employer, said spokesman Denny Hopkins.

Locally, Giant has 1,038 employees in its seven Lehigh County stores and 1,000 in its six Northampton County stores.

Another supermarket chain, Weis Markets of Sunbury, Northumberland County, was just off the list at No. 26, with 925 workers.

Four companies whose major local operations are call centers also made the list. Customers call these centers to do business over the phone. The operations are mostly for customer service and less for outbound telemarketing.

Life insurance company The Guardian is the largest, followed by T-Mobile, which has gone through a few name changes, previously existing as Voicestream Wireless and Omnipoint Communications. First Union National Bank, which will be renamed Wachovia this year, and Aetna health insurance, also have large call centers.

Not included in the top 25 are governments and school districts, which would account for four of the top 10 employers if they were included. Top public-sector employers include U.S. and state governments and county governments in Lehigh and Northampton, all of which employ 2,000 or more, according to records kept by the Lehigh Valley Economic Development Corp.

Some of the largest employers might not be readily recognizable, including No. 8 employer Wood Dining Services. Now owed by Sodexho Alliance of France, Wood provides cafeteria service for companies, colleges, hospitals and other institutions, including many locally. Its sales are more than $600 million a year.

Also, flying below most people's radar is Victaulic Co. of America, which makes pipe couplings at its plant in Forks Township, and Lutron Electronics of Coopersburg, which makes light-switch dimmers. Each employs about 1,200 workers. Sure Fit, known for making couch slip covers, employs 900 locally, and just missed making the largest-25 list.

Conspicuously absent from the list of large employers is Bethlehem Steel, once the undisputed top employer in the region. It counted more than 30,000 workers on its local payrolls after World War II. Today, it's in bankruptcy protection and employs 100 times fewer workers, a mere 300.

About the time steel was king locally, Mack Trucks of Allentown employed about 4,000. Now owned by Volvo, the company today employs half that at 2,000.

But nowadays, that's good enough to be ranked No. 7.

gregory.karp@mcall.com

610-820-6643