Protecting Hearing Starts with Understanding Workplace Noise

October’s National Protect Your Hearing Month is a useful reminder that hearing conservation is not simply about how loud a workplace seems. Understanding risk requires looking at both the intensity of the noise employees encounter and the amount of time they are exposed to it.

For employers, that starts with a relatively straightforward question:

Do you know how much noise your employees are exposed to during a typical workday?

The answer may be less obvious than it sounds. Noise exposure can vary based on how close employees are to operating equipment, the type and duration of work being performed, and the amount of time spent in different areas of a facility. When a worker moves between several areas during a shift or experiences intermittent periods of elevated noise, their overall exposure can be difficult to characterize through observation alone.

According to the National Institute for Occupational Safety and Health (NIOSH), approximately 28% of U.S. workers have been exposed to hazardous noise, with 16%, or approximately 27 million workers, exposed within the last year. About 8% of workers report tinnitus, described as buzzing, rushing or ringing in the ears or head.  

Those numbers underscore why understanding workplace noise exposure is an important part of protecting employees' hearing.

Hearing Risk Is About More Than 
How Loud Something Sounds

NIOSH considers repeated workplace exposures of 85 dBA or higher hazardous and recommends an occupational exposure limit of 85 dBA averaged over an eight-hour shift. 
But sound level is only part of the equation. Duration of exposure matters, too.

NIOSH applies a 3-dB exchange rate. For every 3-dB increase in sound level, the recommended exposure duration is reduced by half. 

That relationship looks like this:

Actual occupational noise exposure should be evaluated based on workplace conditions, employee tasks, exposure duration and applicable regulatory criteria.

This distinction matters because the NIOSH REL is a recommended occupational exposure limit, not an OSHA regulatory compliance threshold. Employers need to understand which criteria apply to their operations rather than treating a single decibel reading as a universal threshold. 

It Is Hard to Manage What You Have Not Characterized

A single sound-level reading provides only a snapshot. To better understand employee exposure, organizations may need to look at how sound varies across a facility, between work activities, and throughout an employee's shift.

NIOSH identifies sound level meters and personal noise dosimeters as two basic instruments for characterizing workplace noise. Sound level meters can help assess area noise and individual sources, while personal dosimeters measure and average noise levels over time to characterize an individual worker's exposure. Noise measurements can also be used to create facility noise maps that show where elevated sound levels occur. 

For employers, that information can help answer practical questions:

• Where are the highest-noise areas or activities?
• Which employees or job functions may experience elevated exposures?
• How does exposure change during a shift?
• Which equipment or processes are significant contributors?
• Where should noise-control efforts be focused?

This is where acoustical analysis becomes more than just measurements. Understanding the source of the sound, the path sound travels, and the people receiving the exposure can help organizations evaluate appropriate noise-control strategies.

GZA's existing noise-consulting capabilities include noise monitoring, sound-generation characterization, attenuation studies, noise mitigation recommendations and design, regulatory compliance, modeling, and industrial hygiene/EHS/OSHA services. 

Hearing Conservation Is Also an EHS Issue

Workplace noise also intersects with occupational health and safety obligations.
Certain cases of occupational hearing loss can have OSHA recordkeeping implications, and OSHA's occupational noise requirements address noise monitoring, audiometric testing, hearing conservation programs, engineering and administrative controls, hearing protection and training. 

That makes effective hearing conservation broader than simply issuing hearing protection. It begins with understanding where exposure occurs and evaluating how that risk can be reduced or managed.

For some organizations, that might mean characterizing noise at its source. For others, it may require understanding how employees move between multiple work areas, how long they spend performing certain tasks, or how changes in equipment and operations affect their daily exposure.

In either case, effective decisions about hearing conservation start with understanding the exposure. 

Bringing Acoustics and Health & Safety Together

Protecting employees' hearing sits naturally at the intersection of acoustical science and environmental health and safety.

GZA's Noise and Acoustics professionals provide expertise in noise monitoring, modeling, impact assessment and mitigation. Combined with GZA's environmental health and safety and industrial hygiene/EHS/OSHA services, we can help organizations characterize workplace noise, understand potential employee exposures, and identify practical opportunities for managing noise and supporting hearing-conservation efforts.

From characterizing workplace noise and employee exposure to evaluating potential controls, GZA's noise-consulting capabilities include noise monitoring, sound-generation characterization, attenuation studies, noise mitigation recommendations and design, regulatory compliance, modeling, and industrial hygiene/EHS/OSHA services.

This National Protect Your Hearing Month, consider starting with one simple question:

Do you know what your employees are hearing throughout their workday?

If the answer isn't clear, a workplace noise assessment can be an important first step toward finding out.

Contact us if you have any questions.