Noise Exposure and Hearing Conservation

Most Canadian jurisdictions have adopted 85 dBA as the permissible exposure limit (PEL) over an 8-hour workday, using a 3 dB exchange rate - meaning every 3 dB increase cuts the allowable exposure time in half. This standard is required under the Canada Occupational Health and Safety Regulations (COHSR, SOR/86-304, Part VII) at the federal level and under provincial regulations including BC OHS Regulation Part 7, Alberta OHS Code Part 23, and Ontario O. Reg. 381/15. Quebec is the exception, using a less protective 90 dBA limit with a 5 dB exchange rate. A single impulse noise peak above 140 dB can cause immediate permanent damage in any jurisdiction.

The earliest and most consistent warning sign is tinnitus - ringing, buzzing, or hissing in the ears after a noisy shift. Workers often dismiss this as a 'noise hangover,' but it is evidence that inner ear hair cells have been stressed or damaged. Other signs include muffled hearing at the end of a shift (temporary threshold shift), difficulty understanding speech even when you can hear that someone is talking, and needing to turn up the TV or phone volume over time. Workers often lose 30–40% of their hearing before they notice anything is wrong, because noise damage starts at high frequencies and progresses slowly over years.

No - Canadian OHS legislation explicitly requires employers to use engineering controls first, before relying on hearing protection devices (HPDs). The federal COHSR, s. 7.5 states that employers must reduce noise exposure 'by engineering controls or other physical means other than hearing protectors, if feasible,' with equivalent language in BC, Alberta, and Ontario regulations. This means options like enclosing machinery, adding acoustic barriers, substituting quieter equipment, or implementing job rotation must all be evaluated and documented before handing workers earplugs. An employer cannot skip engineering controls on cost grounds - the burden is on the employer to show each level of the hierarchy was genuinely assessed.

A formal Hearing Conservation Program (HCP) is required by regulation in BC, Alberta, Saskatchewan, Manitoba, Newfoundland and Labrador, PEI, NWT, Nunavut, and under the federal COHSR - triggered when workers are exposed at or above the action level (typically 85 dBA). An HCP must include five components: noise exposure monitoring using CSA Z107.56-compliant methods, engineering and administrative controls, hearing protection provision and training, audiometric testing, and ongoing worker education. In Ontario, Quebec, New Brunswick, Nova Scotia, and Yukon, an explicit statutory HCP requirement does not exist, but employers' general duty provisions make a well-run HCP the expected standard of due diligence. Training must be provided before a worker enters a noise hazard area for the first time and refreshed at least every two years.

Yes. In jurisdictions where audiometric testing is mandated - including BC, Alberta, Saskatchewan, and under the federal COHSR - employers must provide and pay for both a baseline audiogram and periodic (typically annual) follow-up testing for workers exposed above the action level. Workers have the right to receive their results, and if a significant threshold shift is detected, the employer must arrange referral to a physician. Test records are confidential to the worker. Under the Canada Labour Code, Part II, workers also have the right to report hearing concerns to their employer and to request assessment - and supervisors who discourage workers from exercising these rights may be personally liable under Canadian OHS acts.