Occupational disease and chronic mental stress claims

Region: Ontario Answer # 639

Occupational disease claims

Unlike claims arising from workplace accidents or injuries, compensation claims for diseases allegedly caused by unhealthy conditions or other factors in the workplace, known as occupational disease claims, are difficult to investigate and determine with certainty.

In Ontario, the Occupational Health and Safety Act (OHSA) sets out minimum health and safety standards for workplaces in Ontario and establishes procedures for dealing with workplace hazards.The OHSA has detailed regulations governing many aspects of worker safety, including exposure and handling of biological and chemical agents, and toxic substances.

Occupational disease claims, however, are made under the Workplace Safety and Insurance Act and are handled by the Workplace Safety and Insurance Board (WSIB).

Occupational disease claims may arise from exposure to toxic chemicals or materials, poorly designed equipment and inadequate ventilation, to name a few examples. A recent study estimates as many as 6,000 Ontario workers die every year from occupational diseases. Since the symptoms of many occupational diseases can take years or even decades to surface, the person may not initally associate the disease with their employment and may not realize that they have a valid claim.

Proving the workplace is a significant cause or contributor to a disease, such as cancer, can require the testimony of numerous medical experts, rigorous examination of a patient’s medical history, surveys of other similar workplaces, and lengthy legal arguments. As a result, there are only about 400 claims filed each year in Ontario citing occupational diseases.

That said, workers have received compensation for illnesses ranging from asbestosis to bronchitis to repetitive strain injury. It is interesting to note that compensation has been awarded even in cases where the illness was “significantly” but not entirely caused by the worksite.

Making an occupational disease claim

Anyone can make an occupational disease claim if they think they became ill because of something they did or were exposed to at work. You can make a claim yourself, or through your employer, doctor, union, or someone who you choose to advocate on your behalf. As it could take months, even years, to discover you have a work-related illness, in that regard there is no time limit for filing an occupational disease claim. However, you have six months to file your claim once you learn of your illness or disease.

You must include detailed information in your claim, including:

  • your name, address, date of birth and SIN;
  • the name and location of your employer;
  • all symptoms or illnesses you are claiming;
  • detailed information about the type of work you do and possibly previous employment;
  • what substances and conditions you were exposed to; and
  • names and addresses of all doctors and dates of visits.

Once the WSIB receives your claim, you will be assigned a claim number and an adjudicator from the WSIB Occupational Disease and Survivor Benefits Program will review your claim and make a decision about benefits. The time that an adjudicator will take to make a decision varies, as it depends on how long it takes them to gather workplace information and medical reports.


Chronic mental stress claims

The Stronger, Fairer Ontario Act (Bill 177) is now law. The new law has made changes to the Workplace Safety Insurance Act (WSIA) allowing for chronic mental stress benefits arising out of, and in the course of, employment.

On January 1, 2018, the following transitional provisions (rules) came into effect to determine who is entitled to make a mental stress claim:

  • claims of mental stress arising on or after April 29, 2014, that have not yet been filed, can be filed by workers, or their survivors, until July 1, 2018. Claims filed during this six-month period will be decided under the new mental stress rules,
  • mental stress claims that were already filed (in a timely manner), and have not yet been decided by the Workplace Safety and Insurance Board (WSIB) as of January 1, 2018,  will be decided by the WSIB under the new rules, regardless of when the worker’s mental stress occurred,
  • if a worker (or a worker’s survivor) filed a mental stress claim (in a timely manner), and then filed an appeal (in a timely manner) with the Workplace Safety and Insurance Appeals Tribunal (WSIAT), and if the appeal was still undecided as of January 1, 2018, the WSIAT will send the claim back to the WSIB to re-adjudicate the claim under the new rules, regardless of the date on which the worker’s mental stress occurred.

Both chronic and traumatic mental stress claims can be made under these transitional rules.

If a worker’s claim for mental stress has already been denied by the WSIB or the WSIAT, and the claim does not fall within these transitional rules, the worker cannot re-file the mental stress claims.

For workers in the construction field, the WSIB has partnered with the Construction Safety Association of Ontario (CSAO) to develop a special incident reporting program, called Construction Exposure Incident Reporting (CEIR).

For more information about occupational disease and construction exposure incident claims, contact the Workplace Safety and Insurance Board.



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