SAN JOSE, Calif. - It was more than 30 years ago that John Berggren first caught himself asking people to repeat what they'd just said. It usually happened when Berggren came home from the sheet metal shop.

"I noticed that if I'd had a noisy day, it was hard to hear. I'd have to have my family look at me so I could read their lips," the 55-year-old recalled. At work, it was not unusual for Berggren to spend his whole shift running Pittsburgh machines, and he said he never wore any kind of ear protection.

"It sounds stupid, doesn't it?"

According to the Occupational Safety and Health Administration (OSHA), experiences such as Berggren's are far from unique. OSHA estimates that 30 million Americans are regularly exposed to hazardous levels of noise at work and 10 million have suffered hearing loss as a result.

Gary Batykefer of the Sheet Metal Occupational Health Institute Trust (SMOHIT) said hearing loss is a complaint of many older metalworkers. "Anybody over the age of 50 is going to have some type of hearing impairment, myself included," he said.

Job-related hearing loss costs U.S. companies hundreds of millions of dollars each year in employee disability compensation. And hearing loss can affect more than just a worker's professional life: Some studies have shown that hearing loss caused by work hazards can lead to other health risks. A recent study of construction laborers who have work-related deafness showed many also suffered from impaired balance, making the workers more likely to fall on the job.

'Sound advice'

In response to the problem, SMOHIT has developed a noise safety program for sheet metal workers. "Sound Advice" is a CD-ROM tutorial that can be used by individual workers or as part of a classroom lesson. It explains what causes hearing loss, helps workers identify the early signs of ear damage, simulates hearing loss and shows how to measure noise inside a sheet metal shop.

With press brakes, plasma cutters and coil lines often all running at once, the din inside the typical shop can reach a surprisingly high level, Batykefer said. To figure out exactly how much noise the average metalworker is exposed to, SMOHIT engineers put microphones next to different machines and measured the sound at locations where a worker might be standing.

The decibel readings the engineers took were "pretty dramatic," Batykefer said. Many of the sounds were loud enough to be considered dangerous by OSHA and the National Institute for Occupational Safety and Health (NIOSH).

"The machinery we use, we knew that it was (loud), but there were some situations where you would have figured that you would not have suffered damage," Batykefer said. "For example, when you pull a tin sheet off of a metal rack and it gives you that metal 'whoop,' ¿ well, that's 135 decibels."

OSHA recommends a decibel level of 90 or less; NIOSH says noise should stay below 80 decibels.

The hearing protection program materials include a paper wheel guide to help employees determine what level of noise they're exposed to and what is safe. On one side are types of equipment commonly used in the sheet metal industry. Workers select a task they often perform or assist with. The wheel tells how much noise they're actually experiencing.

For example, workers performing MIG welding on stainless steel ductwork are exposed to up to 89 decibels of sound - above the level recommended by many experts - if they're not wearing any ear protection. With the use of foam earplugs, the exposure level drops to 76 decibels. With foam plugs worn with over-the-ear muffs, the sound is only 64 decibels.

It doesn't take much money to protect your hearing, Batykefer said. "We found out that a lot of times, the cheaper foam earplugs are adequate. For pennies, you can protect yourself," he said.

The other side of the wheel shows what workers' odds are of suffering hearing loss during the next decade if they don't use protection. The chances of losing hearing generally increase with decibel level and the more years of exposure to high levels of noise. While approximately 57 of every 100 workers between the ages of 41 and 43 who regularly expose themselves to noise exceeding 96 decibels will lose some hearing within the next 10 years, employees age 32 to 34 under the same conditions face a 60% chance of hearing loss.

Berggren said he wishes a program like SMOHIT's was around when he was starting in the industry.

"It would have been good to emphasize," he said. "We just worked through it. You were kind of treated like a sissy if you wore (ear protection)."

(SMWIA and SMACNA founded SMOHIT in 1986 to study the effects of asbestos exposure in the sheet metal industry. Today the organization acts as an information clearinghouse on heath and safety issues, offering training programs, instructional CDs and educational courses on topics such as ergonomics, fiberglass exposure and first aid. For more information about SMOHIT programs, write to 601 North Fairfax St., Suite 250, Alexandria, VA 22314 or call 703/739-7130; fax 703/739-7134 or see on the Internet.)