Document name
Occupational Disease
Document number
POL 04/2017

Effective date: October 1, 2017

Application: All Occupational Disease injuries on or after the effective date.

Policy subject: Decision making - Injuries


To establish guidelines for occupational disease injuries.


Policy section content
Section detail
  1. The definition of occupational disease requires two conditions to be met before it is considered an injury, as defined by The Workers’ Compensation Act, 2013 (the “Act”) (Section 2(1)(aa)):
    1. The disease or disorder must have arisen out of and in the course of employment, and
    2. Result from causes or conditions that are:
      1. Peculiar to or characteristic of a particular trade, occupation or industry; or
      2. Peculiar to a particular employment.
  2. The Act provides a definition for “injury”, which includes a “disabling or potentially disabling disorder caused by an occupational disease” (2(1)(r)(iii)).
  3. The Workers’ Compensation Board (WCB) has exclusive jurisdiction to examine, hear and determine all matters arising pursuant to the Act (Section 20). This includes:
    1. Whether any condition or death with respect to which compensation is claimed was caused by an injury (Section 20(2)(a)), and
    2. Whether any injury has arisen out of or in the course of employment (Section 20(2)(b)).
  4. The Act and The Workers’ Compensation General Regulations, 1985 (the “General Regulations”) provide conditions for the presumption of an occupational disease for firefighters. POL 03/2020, Injuries – Firefighters provides guidelines for cancer and cardiac claims for firefighters.
  5. The WCB has established guidelines to determine a worker’s date of injury for both acute and delayed onset injuries (POL 04/2013, Date of Injury).


Policy section content
Section detail
  1. In all cases, the WCB establishes if an injury is work-related by determining if it arose out of and in the course of employment (POL 07/2021, Arising Out Of and In The Course Of Employment)
    1. An injury arises out of employment if it is the result of an activity that has a link to, originates from, or is the result of a worker’s employment and would not have happened if not for a worker’s employment.
    2. An injury occurs in the course of employment when it happens in a time and place linked to employment and if the worker is performing a task which is part of their obligations and purpose of employment.
  2. The WCB will obtain all available information when determining if a disease or disorder arose out of and in the course of employment.
  3. The WCB makes decisions on the real merits and justice of each case and decisions are not bound to follow any legal precedent. If evidence in support of both sides of an issue is approximately equal, the WCB will resolve the issue in favour of the worker (POL 02/2019, Decision Making).
  4. In addition to the following general guidelines, the WCB has established specific guidelines to determine if a disease or disorder is an occupational disease (As per the appendices attached to PRO 04/2017, Injuries – Occupational Disease).

General Guidelines

  1. The WCB considers if a worker’s disease or disorder was the result of exposure to a harmful substance (e.g., asbestos or silica) during employment or because of performing activities for the purpose of their employment.
  2. Exposure to a harmful substance (e.g., asbestos fibres) in the workplace should be reported to the WCB, even if the worker does not initially experience symptoms, seek medical attention or experience earnings loss past the day of exposure.
  3. Exposure or employment activities may result in a worker developing a latent occupational disease. The cause and effect link between the exposure and disease is either known at the time of exposure, or unknown at the time of exposure but a link has since been established through scientific evidence.
  4. A disease or disorder is typically the result of numerous exposures, but may also be the result of a single, usually traumatic exposure, where the cause is easily identified.
  5. A disease or disorder may be the result of both work and non-work causes (e.g., medical conditions, hobbies and exposure in employment not covered by the Act). The WCB will determine claim acceptance based on the degree of exposure or the effect on the disease or disorder by both.
  6. Pre-existing conditions accelerated or aggravated due to a work-related exposure or disease or disorder will be considered under POL 12/2017, Pre-Existing Conditions – Aggravation or Acceleration.
  7. Even if there is a presumption for an occupational disease provided by the Act and the General Regulations, all claims require full file development to determine if it arose out of and in the course of employment.

Permanent Functional Impairment

  1. If an accepted occupational disease claim results in a measurable permanent functional impairment, the worker may be eligible for a Permanent Functional Impairment award as outlined in the PFI – General policy (POL 23/2010).


Cost Relief

  1. Employers may be eligible for cost relief as per POL 03/2021, Second Injury and Re-employment Reserve or POL 05/2014, Occupational Disease Reserve.

Policy references

Policy reference content

Section heading

Legislative Authority

Section detail

The Workers’ Compensation Act, 2013
Sections 2(1)(r), 2(1)(aa), 20, 23, 49

Section heading

Document History

Section detail

(1)    January 1, 2014. References updated in accordance with The Workers’ Compensation Act, 2013.
(2)    August 8, 2004, updated through ADM 03/2004 to reflect that guides concerning certain occupational diseases are to be attached to the procedure in compliance with 2001 Committee of Review recommendation 7.04.
(3)    POL and PRO 11/2003, Injuries – Occupational Disease (effective December 1, 2003 to September 30, 2017).
(4)    POL and PRO 07/1999, Injuries – Occupational Disease (effective February 1, 1999 to November 30, 2003).
(5)    Board Order 40/78, Noise Induced Hearing Loss (effective November 27, 1978). 

Section heading


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