Hearing Conservation

Many work environments are noisy with an endless range and variety of potentially ear-splitting work being performed while on the clock. Simply being exposed to hazardous noise levels can result in hearing loss, by damaging the hair cells directly connected to nerve endings in the inner ear. However, the extent of this damage and severity of hearing loss depend on the amount of noise to which you are exposed and the duration of exposure time.

Depending on the amount, noise can cause hearing loss that is temporary or permanent.

Safety regulations establish a range of noise levels and exposure durations indicating acceptable occupational levels of exposure.

The maximum safe noise level or permissible exposure level (PEL) is 90 decibels, acceptable average exposure over an 8 hour work day. Levels above 90 decibels require employers to furnish hearing protectors.

Levels equal to or below 90 decibels are considered acceptable for industrial noise exposure without the use of hearing protection, unless an employee has suffered a previous hearing loss. For those employees with a previous hearing loss, employers must provide hearing protection at 85 decibels average exposure over an 8 hour work day.

For employees with no hearing loss, hearing protection is optional between 85 and 90 decibels. As an added factor of safety, OSHA established an action level of 85 decibels for instituting a Hearing Conservation Program affecting all those exposed to that noise level.

Employers have certain responsibilities pertaining to protecting the hearing of employees.

Those responsibilities include:

Workplace Surveys: Companies are required to survey the workplace and evaluate individual jobs, to determine the noise levels present.

Warning Signs: Companies are required to post warning signs in areas where high noise hazards exist.

Why is hearing conservation so important?

Unfortunately, there is no fix for permanent hearing loss caused by loud noises

In addition to hearing loss, exposure to high levels of noise can result in physical and psychological stress, reduced productivity, poor communication, and accidents and injuries caused by a worker’s inability to hear warning signals.

Common indications of hazardous noise levels:

• Ringing or buzzing in your ears
• Having to shout to be heard by someone an arm’s length away
• Experiencing temporary hearing loss after leaving a noisy location

The extent of inner ear damage and the severity of hearing loss depend on the amount of noise to which you are exposed and the duration of exposure time. The length of your exposure to noise is as critical as the noise level. In addition to developing gradually over months and years of exposure to less intense noises, hearing loss can occur from a single intense noise such as an explosion.

How loud is too loud?

To put noise levels into perspective, here are the decibels for various noises:

• Conversation: 50 decibels
• Heavy equipment: 90 decibels
• Power saw: 110 decibels
• Jack hammer: 120 decibels
• Rock concert: 130 decibels
• Explosion: 140 decibels

What can be done to protect your hearing?

To reduce worker’s exposure to hazardous noise levels there are several control measures companies can implement:

Engineering Controls

Engineering controls include:

• Placing a shield or barrier between the noise source and employee(s)
• Insulating or muffling the noise source

Administrative Controls

Administrative controls include:

• Posting warning signs
• Limiting the amount of time a worker is exposed to noise

Hearing Protection Devices

Hearing protection should be used when noise levels exceed 90 decibels. If an employee already suffers from hearing loss, hearing protection devices should be used when noise levels reach 85 decibels.

Three types of hearing protection are commonly available:

Ear Inserts: Ear inserts, or “plugs,” block the ear canal. They are available in both pre-formed and custom-made varieties, to fit individual ears, or in hand formable disposable types. Ear inserts provide the best hearing protection in the low frequency sound range.

Ear muffs: Ear muffs fit over the entire outer ear, like headphones. Some earmuffs can be attached to hard hats. Ear muffs offer better protection in the higher frequency ranges, provided they form a good seal around the outer ear.

Canal Caps: Canal caps, also called banded canal caps or ear pods, are cone-shaped caps attached to a headband. They are used for brief periods where easy insertion and removal is necessary. They offer somewhat less protection than ear muffs and ear inserts.

Hearing Conservation Program

If noise levels exceed 85 decibels employers/companies must create a Hearing Conservation Program.

Elements of a Hearing Conservation Program:

• Survey the workplace to determine noise levels present and the hazards to employees associated with those noise levels
• Establish audiometric testing to determine baseline audiograms for affected employees
• Educate employees in hearing conservation requirements
• Provide hearing protection and training in its selection, handling, storage, use and cleaning

Workers who experience buzzing or ringing in their ears during or after exposure to loud workplace noise should report it to their employer immediately.

Wearing hearing protection when exposed to noise above the permissible exposure limit, whether at work or elsewhere, will protect against hearing loss.