Creating a ‘sound’ hearing conservation program
The challenges of limiting noise exposure in the construction industry
- To help reduce noise at the source, NIOSH recommends employers "buy quiet" when choosing machinery and tools.
- Employers should provide a variety of hearing protection options to accommodate workers.
- Audiometric testing helps workers determine if they have hearing loss and provides an indicator of whether the hearing conservation program is effective. If workers are losing their hearing, then other components (such as noise control and hearing protection) need to be revisited.
The sound of one jackhammer, chain saw or nail gun can be bothersome enough. But on a construction site, multiple tools and pieces of heavy equipment may be in use at the same time, creating an abundance of hazardous noise.
Under OSHA rules, the permissible exposure limit for noise in the construction industry is 90 decibels, measured as an 8-hour time-weighted average. At that level, employers are required to provide a hearing conservation program for workers. However, NIOSH advocates lowering the PEL in construction to 85 dBA, which is the cap OSHA sets for general industry.
Torey Nalbone, associate professor and chair of civil engineering at the University of Texas at Tyler, suggests going a step further: “I think for construction, all of the workers should be in some kind of hearing conservation program,” he said.
OSHA outlines specific elements of a hearing conservation program for general industry – including noise monitoring, noise controls and recordkeeping – but not for construction.
Nalbone noted that differences in the work environment make measuring and limiting sound exposure in construction a challenge. For instance, many construction sites are outdoors and the surfaces change constantly, which means the level and intensity of noise is changing as well. The noise is not continuous, so workers may not recognize the danger from brief, loud sounds, such as the popping of a nail gun.
“I have a feeling construction workers sometimes feel that it’s impractical to keep putting earplugs in and taking them out,” Nalbone said. “I think it’s the unprotected noises that we take for granted that are short durations at significant intensity levels – those are the ones that are sneaking up on workers and causing hearing conservation problems.”
The following are elements that can help employers in the construction industry implement an effective hearing conservation program.
Hearing conservation starts with noise exposure monitoring. “If you don’t know how noisy it is, you really can’t have the rest of the program be accurate,” said Rick Neitzel, assistant professor of environmental health sciences at the University of Michigan in Ann Arbor.
The traditional method is to use either a sound level meter to measure sound intensity at a specific moment, or a dosimeter to measure a person’s average noise exposure over time.
Another option is to focus on the noise generated by tasks. Scott Schneider, director of occupational safety and health for the Laborers’ Health and Safety Fund of North America in Washington, cited the ANSI/ASSE A10.46-2013 standard (Hearing Loss Prevention for Construction and Demolition Workers), which calls for assessing the noise exposure from a specific task and instituting appropriate controls and/or providing hearing protection to reduce noise to an acceptable level.
To help with assessments, NIOSH offers a free power tool database that includes sound information for popular construction tools.
Thais Morata, who coordinates the Manufacturing Sector Program of NIOSH’s National Occupational Research Agenda, highlighted an innovative approach to making workers more aware of noise. An article published in the Journal of Health and Safety Research and Practice (Vol. 5, No. 2) describes how Australia’s National Acoustic Laboratories and WorkCover New South Wales developed a simple labeling system to help workers make decisions about hearing protection. A green label signified the noise from a machine was below 85 dBA so no hearing protection was necessary, while a red label was a warning to wear hearing protection.
Researchers noted that sound level meters are a relatively inexpensive way to measure sound for the labeling system. Additionally, Morata said, one of the companies included in the study developed a smartphone application that evaluates the noise level and produces a label. If workers are noticing changes in their hearing at the end of the day, even if it is only temporarily, that means they have been overexposed, according to Morata.
“Maybe you’re not using a noisy tool, but someone next to you is,” she said.
After determining noise levels, the next step is controlling the source of the noise. In addition to administrative controls, such as limiting the amount of time workers spend using noisy equipment, employers should use relevant engineering controls on the equipment.
Morata advised employers to “buy quiet,” which means to take noise levels into consideration when choosing tools and opt for quieter tools when possible.
Neitzel agreed. “Noise is basically just wasted energy,” he said, explaining that quieter equipment often is more efficient, while old or poorly maintained equipment makes more noise. In addition to buying different equipment, spacing out projects may help reduce noise exposure.
“Probably in construction we’re never going to be able to completely eliminate noise, but if we could take some [parts of construction] and make them unexposed, that would be moving in the right direction,” Neitzel said.
He used the example of heavy equipment operators, who can be shielded from hazardous noise levels by being put in a fully enclosed cab.
When noise cannot be eliminated or reduced effectively, workers need to wear hearing protection. Sally Lusk, professor emerita in the School of Nursing at the University of Michigan, has studied hearing protection use in different occupations. She pointed out that people have ear canals of different sizes and shapes, so workers may prefer different styles of hearing protection.
“It’s important that the employer offer a sufficient number of options [so] that the individual worker can select something that will work for him or her,” she said.
Along with giving workers input in hearing protection selection and making sure it is available at the worksite, Lusk said fit-testing is important to determine the actual noise reduction rating that an earplug provides for the person wearing it. The NRR can vary greatly depending on how the earplug is inserted.
“The worker has to take the initiative in protecting their hearing, but the employer needs to provide the resources so they can help educate them about the importance of them doing so,” Lusk added.
Schneider said comfort is a huge factor in whether workers will wear hearing protection. As he put it, “If it’s uncomfortable, they’re not going to use it.”
Whether exposure to high noise is sporadic or continual, construction workers may balk at wearing hearing protection because they worry it will block out important sounds, such as the foreman’s voice or a machine’s alarm.
“One of the chief complaints that construction workers always have is that ‘When I wear hearing protection, I can’t hear what I need to hear,’” Neitzel said. Recent technology can help address this concern. Neitzel said electronic amplifying earmuffs make it possible for workers to communicate in noisy environments by amplifying low-level sounds (such as voices) and filtering out the hazardous noise. Another type of earmuff has a jack for a radio so the foreman can speak to workers while they are wearing hearing protection. Additionally, Neitzel’s research suggests that contractors make the mistake of buying foam earplugs with an NRR of 33 dBA when the sound in the work environment does not warrant that level of protection.
Schneider agreed. “A lot of times the inclination is, ‘Oh, we’re going to get the hearing protection that has the maximum amount of noise reduction,’” he said. “Frankly, for most construction exposures, if you get a decibel reduction of 10 or 15, that’s probably sufficient. You don’t necessarily have to overprotect.”
Annual audiometric testing provides workers with an opportunity to find out if they have experienced any hearing loss (which often occurs gradually and may not be noticed outside of testing until it has decreased considerably). Although valuable, testing requirements sometimes present a challenge among construction workers because of the transient nature of the workforce. Schneider described some of the questions that come with making annual hearing testing mandatory: Who provides the test? Who pays for it? Where are the records kept?
The state of Washington has found one way around this for employers with temporary workers. Neitzel, who previously worked at the University of Washington, said the state’s regulation allows employers to audit their workforce and confirm that workers are wearing hearing protection rather than perform a hearing test for workers. That applies to workers who were hired or transferred to jobs with noise exposure within a year.
Otherwise, “if you have long-term employees, you really should be testing their hearing,” Neitzel added.
He advocates thinking holistically and viewing hearing testing as one piece – not the focus – of a hearing conservation program.
“Audiometric testing is not preventive in any way,” he said. “By the time you catch a hearing loss, it’s already happened. It’s too late. It’s a lagging indicator. By the time you know there’s a problem, the worker has already suffered a lot.”
Evaluating your program
In addition to helping identify hearing loss, audiometric testing helps employers assess the effectiveness of their program.
If an employer has covered the sound monitoring, engineering controls, hearing protection and training, and audiometric testing shows the hearing of the workforce is not changing, that is a good indication the program is effective, Neitzel said. However, he said, if the components of the program are in place and workers’ hearing is still declining, something is wrong and the employer needs to strengthen the program.
Training and education
Training is necessary to help workers understand how and why they need to protect their hearing. Rather than having employees sit down and watch the same video every year, Neitzel recommended changing the materials regularly and quizzing workers to make sure they are retaining the information. Also, take the time to evaluate the effectiveness of training, he said.
When employers make hearing conservation a priority, workers will notice and follow suit. “I think the most important thing is for the employer to communicate the importance of hearing loss prevention,” Schneider said. “By giving people the time and the attention they need to protect their hearing, offering audiometric testing, things like that, that communicates to the worker that this is important.”