A Quieter Future for American Workers?

As printed in Hearing Health, volume 19:3, Fall 2003

By Lee D. Hager

Noise in the workplace is a big issue. The National Institute for Occupational Safety and Health (NIOSH) tells us nearly 30 million people work in noise that could endanger their hearing – that is roughly one worker out of five!

Not surprisingly, a 1991 National Center for Health Statistics survey found that among people with hearing loss aged 65 or younger, most claim exposure to noise as the cause. In addition, it is generally believed that chronic exposure to noise increases stress and can lead to hypertension. It may also negatively affect workers’ attention to task, resulting in decreased productivity.

Spurred on by the realization that the hearing and health of 20 percent of all workers is currently at risk due to work-related noise exposure, the Occupational Safety and Health Administration (OSHA) is revisiting the problem. This move comes after two decades of OSHA complacency over the rising prevalence of hearing loss in the workplace, an era that began with a major shift in focus by the federal agency in the early 1980s.

Disastrous Direction
Noise has been regulated in U.S. industry under OSHA since the late 1960s. The earliest requirements were based on a simple concept: make the workplace safer by making it quieter. Noise control and reduction were paramount.

Concerns about the cost of effectively controlling hazardous noise and the lack of a process to measure the human effects of noise exposure resulted in a major revision to the rules with the adoption of the 1983 Hearing Conservation Amendment. The focus shifted from noise control and reduction to “hearing conservation,” allowing employers to implement a regimen of hearing tests, training and hearing protection. The assumption was that this new approach would provide the same amount of protection but at a lower cost.

Abandoning the goal of quieting workplaces in favor of mandatory testing and ear protection has had chilling outcomes. The 1986 National Occupational Exposure Survey (NOES) revealed that most of industry pays little if any attention to the rule (see figure 1). More recently, a 1998 NIOSH report cited a study that found that 45 percent of companies that should have a hearing conservation program do not. The following text from the report tells more of the story: A recent market analysis found that $180 million is expended annually for hearing protectors and that $120 million is expended for audiograms. So little is spent on noise monitoring and noise control that it is not possible to track expenditures. If a full hearing conservation program were available to all occupational noise exposed American workers, the market should be approaching $1.9 billion per year for every year that noise control is not on the national agenda. Instead, $320 million is spent going through the motions, less than 17% of what is needed.

An additional problem is that a significant portion of the noise-exposed workforce is not covered by the 1983 amendment since it explicitly excludes the construction and mining industries. Clearly, workers in these industries are exposed to significant noise levels but the rules that do cover noise on the construction site and in mines are also inadequate and poorly enforced, resulting in ongoing hearing loss. NIOSH finds that the average 25-year-old carpenter has the hearing ability of a 50-year-old person who has not worked in noise (see figure 2). And over 90 percent of coal miners have hearing impairment by the age of 50 as compared to less than 10 percent of the general population.

As for the effectiveness of hearing protection so strongly emphasized in current regulations, studies indicate that most commercial devices, such as earplugs, earmuffs, etc., do not provide the protection promised. In some cases, on-the-job product performance is as much as 2000 percent lower than noise blocking levels achieved in laboratory tests. Further, many of the devices we use today require workers to manually manipulate them in preparation for use. Workers with arthritic or missing fingers or other dexterity issues could find these devices difficult to use properly.

Controlling the Clamor
To start addressing hazards related to occupational noise exposure, OSHA recently clarified the way that workplace hearing losses must be reported. Standardized reporting should provide for the first time a clear and objective view of the scope and scale of the issue. Concurrently, the Environmental Protection Agency (EPA), the federal entity responsible for evaluating hearing protectors, is looking at improving the way it performs this important job, including its review of new technologies and needs. And at long last, OSHA is considering revising and strengthening the regulations covering the construction industry.

Progress in protecting the American workforce from damaging noise is not limited to the regulatory arena. Exciting things are happening on the research front as scientists shed light through new findings on the physiology and biochemistry of hearing loss. Studies by and with the U.S. military, for example, point to a pharmaceutical approach to hearing loss prevention. Researchers think that damage to the cochlea may be due to free radicals, presenting the possibility of a targeted antioxidant “noise pill.”

Permanence and irreversibility of hearing loss, a long and widely held assumption, is also a hot research topic. Investigators at the Kresge Hearing Research Center at the University of Michigan published a study earlier this year revealing the genetic “switch” that keeps the inner ear’s sensory hair cells from rebuilding themselves after they are damaged. Gene therapy may be used in the future to trick damaged hair cells into repairing and replacing themselves.

In addition, ongoing federally funded studies are showing that exposure to some relatively common workplace chemicals like solvents may either cause hearing loss or make workers more susceptible to the effects of noise.

Finally, NIOSH is undertaking some fascinating research aimed at finding better ways to accommodate hard-of-hearing workers in noisy workplaces. Specialists are working with a range of new and different types of hearing protectors to determine how an industrial hearing conservation program could and should address the needs of hard-of-hearing individuals for protection and communication. Some new technologies actually amplify outside noise when it is quiet but keep the sound that reaches the ear at a safe level.

These are the kinds of regulatory and scientific advances for which many professionals in the hearing conservation field have been advocating. But many areas of concern remain.
Is the relatively small bottom line of occupational hearing loss preventing the issue from receiving more attention? Worker compensation for hearing loss varies from about $2,000 to over $100,000 depending on state jurisdiction and degree of loss. While the dollars eventually add up – in Washington state, for example, hearing loss claims increased twelvefold between 1984 and 1998 – the total amount is dwarfed by other occupational issues like back injuries and ergonomics.

How do we encourage industry to take proactive measures to develop new technologies, quieter machinery and policies that adequately address the risks of hearing loss? However well-intentioned, any standard will be only as good as the implementation allows. Some manufacturers fully comply with all regulations yet continue to see hearing loss increase in their workforce. A small number of companies exceed the minimum requirements, developing their own best practices, facilitating worker involvement and ultimately reducing their incidence of work-related hearing loss.

Answering these questions will take us to the next level in protecting our workers. In the meantime, the small steps we are taking today are important and must be preserved. The industrial revolution’s long legacy of too much noise and too much hearing loss in the workplace may be coming closer to an end as the application of good practice, good research and good regulation makes the American workplace safer for workers and their ears.

Figure 1
Percent of companies providing elements of hearing conservation
requirements, by company size. NOES, 1986.

Figure 2
The average 25-year-old carpenter has the ears of a 50-year-old person
who has not been exposed to noise. NIOSH.

Lee D. Hager, hearing loss prevention consultant for Sonomax Hearing Healthcare Inc., is past president of the National Hearing Conservation Association, past chair of the American Industrial Hygiene Association Noise Committee and has been actively working to protect the hearing of industrial workers since 1986.