Policy
Workers are entitled to benefits for traumatic hearing loss (THL) that results from a work-related accident.
Purpose
The purpose of this policy is to:
- recognize THL as a work-related accident, and
- provide guidance on determining the degree of permanent impairment in allowed THL claims.
Guidelines
Definition
THL is hearing loss of sudden onset experienced after an acute trauma such as:
- exposure to noise from an explosion (acoustic trauma)
- direct trauma to the ear causing damage
- trauma to the head resulting in a severe concussion, or
- exposure to an ototoxic (toxic to the ear) drug or chemical.
*Phaneuf, R. and R. Hetu: An epidemiological perspective of the causes of hearing loss among industrial workers. J. Otolaryngol. 19:31-40, 1990.
Determining the degree of permanent impairment
Maximum medical recovery (MMR)
The WSIB assesses a worker's permanent impairment from THL when MMR has occurred. For more information regarding the determination of MMR refer to 11-01-05, Determining Permanent Impairment. For THL, usually a period of as long as 6 months to a year since the injury may be required to ensure that MMR has been reached.
Rating schedule
The WSIB rates the worker's permanent impairment using the prescribed rating schedule in the American Medical Association Guides to the Evaluation of Permanent Impairment, Third Edition (Revised) (AMA Guides). Average hearing losses are expressed in whole numbers (not rounded) before calculating the permanent impairment using the AMA Guides. To determine the final permanent impairment rating when more than one work-related permanent impairment is present, the WSIB combines the permanent impairment ratings for each impairment using the AMA Guides Combined Values Chart.
Pre-existing hearing loss not related to THL
For guidance on how to determine the degree of work-related permanent impairment resulting from THL for those workers who also have a measurable pre-existing hearing loss condition affecting the same body area, refer to 18-05-03, Determining the Degree of Permanent Impairment.
Occupational noise-induced hearing loss
If a worker has noise-induced hearing loss, refer to 16-01-04, Occupational Noise-Induced Hearing Loss, On/After January 2, 1990.
Application date
This policy applies to all decisions occurring on or after October 7, 2026, for all accidents occurring on or after January 2, 1990.
Document history
This document replaces 15-04-01 dated October 12, 2004.
This document was previously published as:
03-03-02 dated December 1, 1997.
References
Legislative authority
Workplace Safety and Insurance Act, 1997
Sections 2(1), 13(1), 33, 43, 46, 47
Approval
Approved by the Chief Operating Officer, on behalf of the President and CEO on October 1, 2026.