Toronto propane explosion caused by ‘tank-to-tank’ transfer: Fire Marshall

One worker and a firefighter killed in massive blast in the summer of 2008

The Office of the Fire Marshall (OFM) has pinpointed the cause of the massive propane explosion that rocked Toronto in the summer of 2008 following what it calls a “thorough and technically complex investigation.”

On Aug. 10, 2008, an explosion at Sunrise Propane killed one worker and a firefighter responding to the call also died when he suffered a heart attack.

The cause has been identified as a propane leak that resulted from a hose failure during a "tank-to-tank" transfer from one cargo truck to another. The ignition source has not been determined.

Over the course of the lengthy investigation, investigators were faced with many challenges, including asbestos at the scene of the explosion, the decommissioning of thousands of propane tanks at the scene to ensure community and scene safety, and extensive exhibit testing by the OFM.

Recommendations stemming from the OFM's investigation will be sent to the Propane Advisory Team. The Propane Advisory Team was created by the OFM and is comprised of government and agency representatives, propane industry and fire service members to identify regulatory issues and resolve industry and fire department challenges as a result of fire service requirements contained in O. Reg. 440/08 (Propane Storage and Handling).

The recommendations will be shared with the advisory team to help develop strategies for implementing the recommendations and to prevent similar events from happening in the future.

"This incident had a major impact on the community," said Ontario Fire Marshal Pat Burke. "Two people died, thousands were evacuated and property damage and clean up costs were extensive. It is hoped the OFM's investigation can contribute to preventing similar incidents from ever happening again."

The OFM will provide a redacted copy of the report, which is very technical in nature, upon request and will be releasing an executive summary outlining key findings of its investigation shortly.

Sixteen OFM staff participated including fire investigators, supervisors, forensic fire protection engineers, coordinators and fire protection specialists.

Throughout the investigation the team worked closely with the Office of the Chief Coroner, Toronto Police Service, Toronto Fire and Emergency Services, City of Toronto Facilities Management, Technical Standards and Safety Authority, the Ministry of Labour and the Ministry of the Environment.

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