Tips to address the most common workplace injury - hearing loss

A report from the Centers for Disease Control and Prevention (CDC) warns that work-related hearing loss is the most common work injury and over 22 million workers a year are exposed to unsafe levels of noise. Noise-induced hearing loss can't be reversed, but it is 100% preventable.

OSHA's permissible exposure limit for noise is 90 dBA for an eight-hour period. For every 5 dBA increase, the agency's Occupational Noise Exposure Standard calls for workers to cut their maximum exposure time in half. For example, 95 decibels is safe for up to four hours, 100 decibels is safe for up to two hours, and so on. There are some who argue that these standards are too low and OSHA is planning to review the construction standards, which differ from general industry standards.

For general industry workers who are exposed to noise for eight hours a day at or above a time-weighted average of 85 decibels, OSHA requires employers to provide notification, audiometric testing and free hearing protectors. Employers also have to offer training programs for affected workers.

The Department of Labor estimates that workers' compensation payments for hearing loss disability total $242 million a year. Employers were penalized $1.5 million for failing to ensure their workers were protected against hearing damage. Even a short-term exposure can cause serious damage or tinnitus, which is the perception of sound in one or both ears, or in the head, when there's no other source of sound. Hearing loss leads to significant safety issues in the workplace as well as psychological and social effects such as frustration and feelings of isolation.

While the industries with the most hearing loss amongst workers are mining, construction, and manufacturing, a study by NIOSH found:

• Workers in agriculture, forestry, fishing and hunting faced "significantly higher risks" for hearing difficulty, tinnitus and the occurrence of both conditions.
• Workers in life, physical and social science occupations faced a significantly higher risk for hearing difficulty.
• Workers in architecture and engineering roles faced a significantly higher risk for tinnitus.

OSHA offers the following signs that a workplace might be too noisy:

• Workers hear ringing or humming in their ears at the end of the workday.
• A worker must shout to be heard by another worker an arm's length away.
• Workers notice temporary hearing loss at any point when leaving work.

Baseline and annual audiograms may help participants in a hearing conservation program determine if workers are avoiding hearing loss. If a worker shows a change in hearing test results - described by experts as a "standard threshold shift" - the employer is required to fit or refit the worker for hearing protection, train the worker on proper use, and ensure the worker wears the protection.

Mark Cullen, a professor at Stanford University who explores workplace hazards, found in a study that the employees who suffer most from hearing loss were those who were working in jobs involving moderate noise levels instead of high-noise environments. "At very high noise exposures, people very faithfully wear hearing protection and at low noise situations, people don't," he said. He notes employers could build noise barriers or eliminate noisy equipment, but old factories often choose to just offer hearing protection gear.

While PPE can be effective, the major problems are:

• Easy to remove
• Discomfort
• Poor fit
• Trouble inserting ear plugs
• Not individualizing protection can lead to overprotection, which can add to the safety issues of being unable to hear warning signals, etc.
• Using PPE that is not independently tested to verify noise reduction ratings
• Not researching new technologies

He said there is also existing technology that will measure noise exposure in real time in each worker's hearing protection gear, with lights that will flash when the level becomes hazardous. The data can be downloaded each day to monitor daily exposures.

Some tips for employers:

• Do area noise monitoring regularly and look at potential engineering and administrative controls for noise issues before distributing hearing protection. It can be more efficient and effective.
• Become familiar with NIOSH's Buy Quiet Initiative
• Stay current with appropriate technologies
• Monitor maintenance - older machinery can shake, rattle, and bump if not properly maintained
• Properly train workers and provide sound level meters
• Promote to younger workers how important it is to protect their hearing
• Make employees part of the solution