Occupational Noise Exposure: Protecting Workers from Noise-Induced Hearing Loss

Overview

The Center for Disease Control (CDC) estimates that 22 million workers are exposed to potentially damaging noise at work each year. Occupational noise exposure is a significant issue in various industries, including construction, manufacturing, and transportation.

Whether you’re working at a sports venue, an airport tarmac, or operating heavy machinery, noise-induced hearing loss is entirely preventable with proper measures.

Hearing loss not only affects communication but can diminish quality of life, causing frustration and isolation. The good news is that noise-induced hearing loss (NIHL) is preventable through awareness, appropriate safety standards, and effective noise control programs.

Know Your Workplace Noise Levels!

An essential first step in protecting workers is identifying when noise levels become hazardous. Noise is considered potentially dangerous if you need to raise your voice to communicate with someone 3 feet away. The Occupational Safety and Health Administration (OSHA) defines 85 decibels (dB) as the threshold for harmful noise over an eight-hour workday.

Several instruments can measure workplace noise levels:

• Sound level meters measure noise intensity in a specific area.
• Noise dosimeters track noise exposure over time, commonly worn by employees to record levels they experience throughout the day.
• Octave band analyzers break down noise into different frequency components to identify specific sources of harmful noise.

Standards

OSHA mandates that employers implement a Hearing Conservation Program when workplace noise exposure exceeds 85 dB over an eight-hour period, also known as an 8-hour time-weighted average (TWA). The goal of this program is to prevent hearing loss and to equip workers with the knowledge and hearing protection devices (HPDs) to safeguard themselves.

OSHA’s standard, 29 CFR 1910.95, outlines the noise exposure limits and required measures employers must take, including hearing protection, education, and regular hearing assessments for workers.

Health Effects of Occupational Noise Exposure

Repeated exposure to loud noise kills the nerve endings in the inner ear, leading to permanent hearing loss that cannot be reversed with surgery or medicine. This type of hearing loss usually occurs gradually, so many workers may not notice the damage until it’s too late.

Other effects of noise exposure include:

• Tinnitus: A persistent ringing or buzzing in the ears.
• Reduced ability to hear high-frequency sounds: This can severely impact a worker’s ability to communicate effectively.
• Increased fatigue and stress: Constant exposure to loud environments can lead to reduced focus and concentration, increasing the risk of accidents.

Understanding how the ear works is critical for protecting it. The ear is divided into three parts: the outer ear, middle ear, and inner ear. Sound waves travel through these structures, causing vibrations that translate into the sounds we hear. Exposure to loud noises can damage the sensitive hair cells in the inner ear, leading to permanent hearing damage.

Exposure & Controls

Noise is essentially unwanted sound that can be harmful at high levels. Prolonged exposure to sound over 85 dB is generally considered hazardous, and many work environments surpass this threshold.

Common noise sources in workplaces include:

• Heavy machinery
• Power tools
• Engines
• Construction equipment

Controlling Noise Exposure

There are several ways to minimize worker exposure to excessive noise and prevent hearing loss:

1. Use quieter machines: Newer, more advanced equipment often has built-in noise-reducing features. Replacing old machinery can significantly reduce workplace noise.
2. Isolate the noise source: Placing loud machines in enclosed areas or soundproof rooms can limit the amount of noise exposure in other parts of the workplace.
3. Limit worker exposure: Rotating employees through different tasks or reducing the amount of time spent in high-noise areas can prevent prolonged exposure.
4. Provide effective hearing protection: Earplugs or earmuffs designed for industrial use can block harmful noise, keeping employees’ hearing safe.

Hearing Conservation Program

Under OSHA’s Noise Standard, employers must reduce noise exposure using one or a combination of the following methods:

• Engineering controls: Physical changes to equipment or the environment to reduce noise at the source.
• Administrative controls: Rotating workers through high-noise areas to reduce their exposure time.
• Hearing Protection Devices (HPDs): Earplugs and earmuffs that attenuate noise levels, bringing them within safe limits.

Table G-16 and Table G-16A of 29 CFR 1910.95(b)(1) provide guidelines for acceptable noise exposure levels. If noise levels cannot be sufficiently reduced through engineering or administrative controls, HPDs are required to protect workers’ hearing.

Hearing Loss in Construction

The construction industry is particularly susceptible to noise-related issues. Heavy equipment like jackhammers, bulldozers, and concrete saws generate high levels of noise, often well above the safe limit. OSHA has specific regulations for noise in construction, which are outlined in standards like 29 CFR 1926.52. Employers must implement noise monitoring, provide hearing protection, and educate workers on the dangers of occupational noise exposure.

Hearing Protection Devices in Construction

Providing appropriate earplugs, earmuffs, or canal caps is crucial for construction workers who are frequently exposed to high decibel levels. These devices must be regularly inspected and replaced as needed to ensure their effectiveness.

Additional Resources

For more detailed information on hearing conservation, noise exposure, and protective strategies, several resources are available:

• OSHA’s Noise Standard (29 CFR 1910.95): Detailed regulations on occupational noise exposure.
• NIOSH Sound Level Meter App: A free tool that allows workers to measure sound levels using their mobile devices.
• CDC Workplace Safety & Health Topics: A comprehensive source for workplace safety information, including noise exposure.

Workers’ Rights

Workers have the right to a safe workplace, including protection from excessive noise exposure. OSHA’s whistleblower protections ensure that employees can report unsafe working conditions without fear of retaliation. If you believe your workplace is too loud and hearing protection is not being provided, you can file a complaint with OSHA to ensure corrective actions are taken.

Conclusion

Occupational noise exposure is a critical issue that requires attention and action from both employers and employees. With the right hearing conservation programs, regular monitoring, and effective use of protective devices, noise-induced hearing loss is entirely preventable. Remember, hearing loss is permanent—so take the necessary steps today to protect your ears.

For more resources and tools on workplace safety, visit ohse.ca.