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.
How loud is too loud?
The maximum safe noise level or permissible exposure limit (PEL) is 85 decibels, acceptable average exposure over an 8-hour workday. Levels above 85 decibels require employers to furnish hearing protectors. Levels equal to or below 85 decibels are considered acceptable for industrial noise exposure without the use of hearing protection unless an employee has suffered a previous hearing loss.
Employers have certain responsibilities pertaining to protecting the hearing of employees.
Those responsibilities include:
Audiometric Surveys: Employers are required to survey the workplace and evaluate individual jobs, to determine the noise levels present.
Warning Signs: Employers 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.
To put noise levels into perspective, here are the decibels for various noises:
- City traffic: 70 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 include:
- Placing a shield or barrier between the noise source and employee(s)
- Insulating or muffling the noise source
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 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.
Earmuffs: Earmuffs fit over the entire outer ear, like headphones. Some earmuffs can be attached to hard hats. Earmuffs 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 earmuffs 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.
- 20 minutes
- Format: Video
- English , French Canadian
- Noise and Hearing
- Canadian OH&S Regulations Noise Exposure Limits
- Hearing Protectors
- Hearing Conservation Program
- Canada Occupational Health and Safety Regulations, Part 7 - Levels of Sound
- CSA Z-94.2-14 (R2019),CSA Z-94.2 - Hearing protection devices - Performance, selection, care, and use
- CSA Z1007:22, Hearing Loss Prevention Program (HLPP) Management