Work-related hearing loss continues to be a critical workplace safety and health issue. In fact, it has been listed as one of 21 priority areas for research in the next century by NIOSH and the occupational safety and health community.

Noise-induced hearing loss is one of the most common occupational diseases, and the second most self-reported occupational illness or injury. While any worker can be at risk for noise-induced hearing loss in the workplace, industries with high numbers of exposed workers include: agriculture; mining; construction; manufacturing and utilities; transportation; and military.

“More attention is being paid to noise in the workplace today than ever before,” says Ben Forrest, president of Forrest Sound Products in Bellevue, WA.

While hearing protection devices are in wide use in industrial settings, said Forrest, it’s still important for companies to develop “complete, innovative solutions to noise and vibration challenges in order to protect themselves from hearing loss lawsuits in the future.”

Removing hazardous noise from the workplace through engineering controls (e.g. installing a muffler or building an acoustic barrier) is the most effective way to prevent noise-induced hearing loss, according to the National Institute of Occupational Safety and Health. Still, hearing protectors such as earplugs and ear muffs should be used when it is not feasible to otherwise reduce noise to a safe level.

NIOSH recommends hearing loss prevention programs for all workplaces with hazardous levels of noise. These programs should include noise assessments, engineering controls, audiometric monitoring of workers’ hearing, appropriate use of hearing protectors, worker education, recordkeeping, and program evaluation.

The following is an outline of evaluative actions taken by Forrest Sound Products after a request for assistance following an OSHA noise survey:

• Evaluation of OSHA report and preliminary site inspection;

• Evaluate customer goals, their complexity and practicality;

• Evaluate their budget process;

• Conduct a preliminary noise survey;

• Take photographs;

• Determine preliminary dimensions;

• Conduct preliminary discussions with operators/management of benefits;

• Establish a prioritization of treatment.

After conducting a survey, we meet with the plant owner and attack the loudest part of the plant first, said Forrest, making sure to include the folks doing the work. Collaboration is essential, he added. “You’re not just dealing with noise, but with interferences in the workplace as well. You can’t always put an enclosure up.”

Failures or deficiencies in hearing conservation programs can often be traced to inadequacies in the training and education of noise-exposed employees and those who conduct elements of the program. The following checklist can help improve a deficient program:

1. Has training been conducted at least once a year?

2. Was the training provided by a qualified instructor?

3. Was the success of each training program evaluated?

4. Is the content revised periodically?

5. Are managers and supervisors directly involved?

6. Are posters, regulations, handouts, and employee newsletters used as supplements?

7. Are personal counseling sessions conducted for employees having problems with hearing protection devices or showing hearing threshold shifts?

Data indicate that employees who refuse to wear hearing protectors or who fail to show up for hearing tests frequently work for supervisors who are not totally committed to the hearing loss prevention programs. The following will help supervisors prevent hearing loss:

1. Have supervisors been provided with the knowledge required to supervise the use and care of hearing protectors by subordinates?

2. Do supervisors wear hearing protectors in appropriate areas?

3. Have supervisors been counseled when employees resist wearing protectors or fail to show up for hearing tests?

4. Are disciplinary actions enforced when employees repeatedly refuse to wear hearing protectors?

For noise measurements to be useful, they need to be related to noise exposure risks or the prioritization of noise control efforts, rather than merely filed away. In addition, the results need to be communicated to the appropriate personnel, especially when follow-up actions are required. Consider the following:

1. Were the essential/critical noise studies performed?

2. Was the purpose of each noise study clearly stated? Have noise-exposed employees been notified of their exposures and appraised of auditory risks?

3. Are the results routinely transmitted to supervisors and other key individuals?

4. Are results entered into health/medical records of noise exposed employees?

5. Are results entered into shop folders?

6. If noise maps exist, are they used by the proper staff?

7. Are noise measurement results considered when contemplating procurement of new equipment? Modifying the facility? Relocating employees?

8. Have there been changes in areas, equipment, or processes that have altered noise exposure? Have follow-up noise measurements been conducted?

9. Are appropriate steps taken to include (or exclude) employees in the hearing loss prevention programs whose exposures have changed significantly?

Controlling noise by engineering and administrative methods is often the most effective means of reducing or eliminating the hazard.

In some cases engineering controls will remove requirements for other components of the program, such as audiometric testing and the use of hearing protectors.

1. Have noise control needs been prioritized?

2. Has the cost-effectiveness of various options been addressed?

3. Are employees and supervisors appraised of plans for noise control measures? Are they consulted on various approaches?

4. Will in-house resources or outside consultants perform the work?

5. Have employees and supervisors been  counseled on the operation and maintenance of noise control devices?

6. Are noise control projects monitored to ensure timely completion?

7. Has the full potential for administrative controls been evaluated? Are noisy processes conducted during shifts with fewer employees? Do employees have sound-treated lunch or break areas?

When noise control measures are infeasible, or until such time as they are installed, hearing protection devices are the only way to prevent hazardous levels of noise from damaging the inner ear. Making sure that these devices are worn effectively requires continuous attention on the part of supervisors and program implementers, as well as noise exposed employees. Ask the following questions:

1. Have hearing protectors been made available to all employees whose daily average noise exposures are 85 dBA or above? (NIOSH recommends requiring HPD use if noises equal or exceed 85 dBA regardless of exposure time.)

2. Are employees given the opportunity to select from a variety of appropriate protectors?

3. Are employees fitted carefully with special attention to comfort?

4. Are employees thoroughly trained, not only initially but at least once a year?

5. Are the protectors checked regularly for wear or defects, and replaced immediately if necessary?

6. If employees use disposable hearing protectors, are replacements readily available?

7. Do employees understand the appropriate hygiene requirements?

8. Have any employees developed ear infections or irritations associated with the use of hearing protectors?

Are there any employees who are unable to wear these devices because of medical conditions? Have these conditions been treated promptly and successfully?

9. Have alternative types of hearing protectors been considered when problems with current devices are experienced?

10. Do employees who incur noise-induced hearing loss receive intensive counseling?

11. Are those who fit and supervise the wearing of hearing protectors competent to deal with the many problems that can occur?

12. Do workers complain that protectors interfere with their ability to do their jobs? Do they interfere with spoken instructions or warning signals? Are these complaints followed promptly with counseling, noise control, or other measures?

13. Are employees encouraged to take their hearing protectors home if they engage in noisy non-occupational activities?

14. Are new types of or potentially more effective protectors considered as they become available?

15. Is the effectiveness of the hearing protector program evaluated regularly?

16. Have at-the-ear protection levels been evaluated to ensure that either over or under protection has been adequately balanced according to the anticipated ambient noise levels?

17. Is each hearing protector user required to demonstrate that he or she understands how to use and care for the protector? The results documented?

An effective way of reducing noise is to locate noisy equipment behind purpose-built barriers. The barriers can be constructed on the work site from common construction building material (plywood, block, stacks or spoils), or the barriers can be constructed from commercial panels lined with sound absorbing material to achieve the maximum shielding effect possible.

To be effective, the length of the barrier should be greater than its height. The noise source should not be visible and barrier should be located as close as possible to either the noise source or the receiver.

“Usually employees have to deal with noise all day long,” said Forrest. “If you can apply a control that does not interfere with their work, they’ll be happy with the solution. Excessive noise saps energy and concentration, making the workplace less safe because you can’t hear warnings. Reduce the noise, and you can increase productivity and attention spans.”