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News release

Associated links (R18Q0046)

Uncontrolled movement led to May 2018 derailment at Sept-Îles Yard, Quebec

Dorval, Quebec, 15 August 2019 — In its investigation report (R18Q0046) released today, the Transportation Safety Board of Canada (TSB) found that accumulated corrosion inside a coupler led to a May 2018 uncontrolled movement and derailment of rolling stock on non-main track at Sept-Îles Yard, in Sept-Îles, Quebec.

On 1 May 2018, at approximately 1425 Eastern Daylight Time, a cut of 17 empty mixed freight cars uncoupled from a yard assignment train at the marshalling yard of the Quebec North Shore and Labrador Railway (QNS&L) in Sept-Îles, Quebec. The cut of cars ran uncontrolled and headed toward the yard shop. The first four of the 17 cars left the track when going over a sliding derail, and rolled onto a concrete surface. The lead car went through the bay door and entered the repair shop, striking a parked track unit, which derailed. The cut of cars travelled a total distance of about 1700 feet. There were no injuries and no dangerous goods were involved.

The TSB’s investigation found that when the movement was coupled to an ore car, the coupler lock likely dropped only partially into position due to the accumulated corrosion. When subsequent movements subjected the coupler to in-train forces, the engaged edges of the lock and the coupler slipped, causing the release of the lock and the unintended opening of the coupler. In addition, switching operations at Sept-Îles Yard that day were being performed while the movement’s brake pipe was not charged with air. The emergency brakes were thus not available.

For the protection of employees, a sliding derail had been installed approximately 60 feet away from the shop on the track leading to the door of bay No. 4, in compliance with industry best practices. The investigation determined that, due to the presence of a concrete surface surrounding the shop, there was only approximately 20 feet of ballast available to trap and stop the derailed cars—an amount that proved insufficient.

Following this occurrence, QNS&L issued a circular stating that rolling stock must be charged with air and have sufficient operational brakes. QNS&L also implemented new lock-out procedures for the protection of employees and initiated a project for the replacement of sliding derails with switch derails.

See the TSB investigation page for more information.


The TSB is an independent agency that investigates air, marine, pipeline, and rail transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

For more information, contact:
Transportation Safety Board of Canada
Media Relations
Telephone: 819-360-4376
Email: media@tsb.gc.ca