News release

Freight car structural failure led to 2019 train derailment in tunnel between Canada and the United States

Richmond Hill, Ontario, 18 December 2023 — Today, the Transportation Safety Board of Canada (TSB) released its investigation report (R19T0107) into the main-track train derailment near Sarnia, Ontario.

On 28 June 2019, a Canadian National Railway Company (CN) freight train was proceeding through the CN Paul M. Tellier Tunnel en route from Sarnia, Ontario to Port Huron, Michigan, United States (U.S.) when a total of 45 cars and one locomotive derailed, including one tank car that released 12 000 U.S. gallons of sulphuric acid. There were no injuries.

The investigation determined that the accident occurred when a bathtub gondola car sustained a structural failure and the leading end collapsed, resulting in a derailment in the tunnel on the Canadian side of the border. The car was built in 1978 and was modified in 2012 for use in scrap steel service. At the time of its failure, the car had a number of pre-existing defects that contributed to its reduced structural integrity. Visual examination determined that the defects were not recent but had developed over a period of time.

Despite its deteriorated condition, the car travelled frequently within, and between, Canada and the U.S. and was interchanged between railways 16 times in the six months preceding the accident. In the three months prior to the accident, it received 24 certified car inspections and had numerous pull-by inspections, with no significant structural defects noted.

Neither the Canadian freight car safety rules, the U.S. freight car safety standards, nor the Association of American Railroads (AAR) Interchange Rules contained limits to identify defects to certain structural components of freight cars, such as those present in the failed gondola car. Thus, the structural defects did not prevent the car from remaining in service.

Safety actions taken

Following this accident, the TSB issued four rail safety advisory letters (RSA):

1. RSA 08/19: issued 19 August 2019, advises Transport Canada to ensure that railways have specific instructions or guidance in their emergency procedures for conducting train inspections following a derailment in a tunnel involving dangerous goods.
2. RSA 09/19: issued 16 September 2019, advises Transport Canada and the U.S. Federal Railroad Administration to ensure that railways and car owners have procedures in place to identify, inspect, and repair (as required) bathtub gondola cars that are equipped with stub sills, particularly those being used in scrap iron and steel service, which were constructed in the late 1970s and early 1980s.
3. RSA 06/20: issued 11 September 2020, advises Transport Canada to ensure that all railways have adequate practices in place to effectively manage in-train forces.
4. RSA 07/20: issued 11 September 2020, advises Transport Canada and the U.S. Federal Railroad Administration to ensure that all bathtub gondola cars built by Berwick Forge and that operate in North America, are identified, located, and examined to ensure continued safe railway operations.

In response to RSA 08/19, CN informed the TSB that it installed permanent visual and audible alarms in the tunnel’s portals, which will alert employees to the presence of toxic gases. CN also issued a summary bulletin to its employees, which included new emergency procedures that must be followed by crew members in the event of an emergency in a tunnel.

Additionally, Transport Canada wrote to the Railway Association of Canada and the Western Canadian Short Line Railway Association recommending that Canadian railways ensure that their equipment, procedures, and instructions be reviewed and updated, as required, to ensure employee safety.

In response to RSA 09/19 and RSA 07/20, Transport Canada contacted the AAR regarding the issues mentioned in these two RSAs and continued to follow up with the AAR to ensure that all of the cars identified in the AAR-issued Maintenance Advisory MA-0188 were inspected. The 2020 AAR Interchange Rules were revised to include defect limits for additional freight car structural components.

Following the derailment, CN inspected 416 of the 2130 identified cars of similar type and vintage to the bathtub gondola car that failed in the tunnel and that were being used in scrap iron and steel service in North America. CN identified defects in 149 of the 416 cars (36%).

Learn more about the investigation findings and safety actions taken.