Overview: Managing Noise Hazards Under Ontario’s Occupational Health and Safety Act
Noise is one of the most common—and most underestimated—workplace hazards. In Ontario, employers are required under the Occupational Health and Safety Act (OHSA) to protect workers from exposure to excessive noise that can cause permanent hearing loss or other health effects.
Ontario Regulation 381/15: the occupational noise exposure limit and requires employers to implement protective measures to control worker exposure and sets out what employers must do to assess, control, and monitor noise levels in the workplace.
Whether you manage a manufacturing plant, warehouse, or institutional facility, understanding how this regulation applies to your operations is essential to maintaining a safe and compliant work environment.
Noise assessments and hearing conservation programs are key to compliance. Learn more about THEM’s expertise: Noise and Hearing Conservation Services – T. Harris Environmental Management Inc.
What Ontario Regulation 381/15 Covers
Ontario Regulation 381/15 applies to all workplaces governed by the OHSA, regardless of industry. It establishes the maximum allowable noise exposure and requires employers to implement measures to keep workers’ exposure below those limits.
Key Points of the Regulation
- Noise Exposure Limit: Workers must not be exposed to a sequivalent sound exposure level greater than 85 dBA (L_ex,8), representing the time-weighted average noise exposure over an eight-hour work shift.
- Exposure Duration: If noise levels exceed 85 dBA, the maximum allowable exposure time decreases significantly (e.g., 88 dBA = 4 hours, 91 dBA = 2 hours)decreases according to a 3-dB exchange rate, meaning that every 3 dB increase in sound level halves the allowable exposure time (e.g., 88 dBA ≈ 4 hours, 91 dBA ≈ 2 hours).
- Control Measures: Employers must take all reasonable measures, including engineering controls, work practices, and hearing protection devices, to protect workers from hazardous sound levels.ve equipment (PPE).
- Audiometric Testing: Employers should consider implementing a hearing conservation program, which may include audiometric testing, where workers are exposed to hazardous noise levels.
- Worker Information and Training: Employers must provide instruction and training on noise hazards and the proper use, care, and limitations of hearing protection devices.
In short, the regulation makes noise control a proactive employer responsibility rather than a reactive measure after damage occurs.
Employer Responsibilities in Plain Language
Under Ontario Regulation 381/15, employers must:
- Employers must determine worker noise exposure where necessary to identify appropriate protective measures.
- Implement controls to reduce exposure using engineering solutions (e.g., sound-dampening, isolation) and administrative measures (e.g., rotating tasks, limiting exposure time).
- Hearing protection devices must be provided where engineering or administrative controls cannot adequately reduce exposure below the limit.
- Inform and train workers about the hazards of noise and proper use of hearing protection.
- Maintain documentation of noise assessments, protective measures, and worker training where applicable.
Failure to address noise hazards can lead not only to regulatory penalties but also to long-term health consequences for workers—including permanent, irreversible hearing loss.
The First Step: Conducting a Noise Assessment
A Noise Assessment is commonly used to determine whether worker exposure may exceed the regulatory limit and to identify appropriate control measures.
What a Noise Assessment Includes
- Sound level monitoring using calibrated noise dosimeters or sound level meters
- Mapping of noise levels across different work areas
- Evaluation of work processes and equipment that contribute to exposure
- Recommendations for engineering, administrative, or PPE controls
- Documentation suitable for Ministry of Labour review or internal audits
THEM’s Expertise
With more than 45 years of occupational hygiene experience, T. Harris Environmental Management Inc. (THEM) provides accurate, reliable noise assessments and supports clients in implementing full hearing conservation programs.
Our specialists help clients:
- Measure and analyze workplace noise exposure
- Design noise control solutions tailored to their operations
- Implement hearing protection fit-testing and training programs
- Establish recordkeeping and follow-up testing schedules
THEM’s Occupational Hygienists make complex regulations easier to understand and apply—helping you protect workers and maintain compliance.
Learn more about our Noise and Hearing Conservation Services →
Noise Exposure Compliance Checklist
| Step | Compliance Action | Status |
| 1 | Identify areas or tasks with potential high noise exposure | ☐ |
| 2 | Conduct a Noise Assessment (dosimetry or area measurements) | ☐ |
| 3 | Compare exposure results to the 85 dBA, 8-hour legal limit | ☐ |
| 4 | Implement engineering and administrative controls where possible | ☐ |
| 5 | Provide and enforce the use of approved hearing protection | ☐ |
| 6 | Include workers in a hearing conservation and audiometric testing program | ☐ |
| 7 | Train workers and supervisors on noise hazards and safe practices | ☐ |
| 8 | Review and update noise assessments regularly | ☐ |
If any of these items remain unchecked, THEM can help you assess your current exposure levels and develop a clear, compliant noise control plan.
Next Steps for Employers and Safety Leaders
Noise hazards can exist in any workplace—from industrial facilities and construction sites to schools, hospitals, and warehouses. By taking a proactive approach, employers can prevent hearing loss, protect workers, and maintain compliance with Ontario’s regulations.
Start by assessing your current noise exposure levels and reviewing your existing controls. If your facility has not been assessed recently, a Noise Assessment from THEM is the most effective way to establish a baseline and identify where improvements can be made.
Partnering with experts ensures that your workplace not only meets the legal standard but also fosters a safer, more productive environment for everyone.
Take control of workplace noise before it becomes a problem.
Request a Noise Assessment or Hearing Conservation Consultation →