MRO Magazine

Companies fined $90,000 after workers collapse at oil refinery

Health & Safety

April 22, 2015
By Bill Roebuck


Sarnia, ON – Shell Canada Limited/Shell Canada Limitée and CEDA International Corporation pleaded guilty and were fined a total of $90,000 after two workers collapsed.

In early 2013, Shell hired CEDA, an Alberta-based company that provides chemical-cleaning services to industrial facilities, to clean heat exchanger tubes at Shell’s Sarnia Manufacturing Centre, an oil refinery in Corunna, ON.

On April 26, 2013, CEDA workers were at the refinery, cleaning two tubes. The tubes were placed into a vat, which was then filled with a sulphuric acid solution. Just after the acid had been added, the workers’ hydrogen sulphide (H2S) monitors began sounding. They also noticed a strong smell emanating from the vat.

Two CEDA employees closest to the vat helped each other get to a safe distance. Both workers suffered dizziness, disorientation and briefly collapsed. One of the workers reportedly briefly lost consciousness. A third CEDA employee was able to leave the area. All three workers were taken to hospital and released the same day.


A Ministry of Labour investigation found that the workers were exposed to H2S gas. The scales on the tubes contained iron sulphide. When the iron sulphide came into contact with the sulphuric acid solution, a chemical reaction led to the release of H2S gas into the atmosphere.

The investigation found that although the workers were wearing personal monitors to warn of any potential release, they were not wearing any personal protective equipment capable of protecting them from the effects of exposure to H2S gas. The workers were also not informed they might be exposed to H2S gas as a result of cleaning the tubes in an acid bath.

Shell Canada Limited/Shell Canada Limitée pleaded guilty to failing as an employer to provide information, instruction and supervision to a worker to protect the health and safety of the worker. CEDA International Corporation pleaded guilty to failing as an employer to acquaint a worker, or a person in authority over a worker, with the hazard of hydrogen sulphide.

Shell Canada Limited/Shell Canada Limitée was fined $40,000 by Justice of the Peace Anna Marie Hampson in Sarnia court on April 20, 2015. CEDA International Corporation was fined $50,000 on that same day. In addition to the fine, the court imposed a 25% victim fine surcharge as required by the Provincial Offences Act. The surcharge is credited to a special provincial government fund to assist victims of crime.