Complete failure of cracked rail led to Jan. 2015 CP derailment

Written by Mischa Wanek-Libman, editor
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TSB

A complete failure of an already-cracked rail led to the January 2015 derailment of a Canadian Pacific train near Nipigon, Ontario, according to the Transportation Safety Board of Canada (TSB).

The investigation report by the TSB also made findings about the performance of pressure tank cars during derailments and the risks to train crews when dangerous products are released. The accident occurred Jan. 13, 2015 when 21 cars, including seven loaded with propane, derailed. One tank car lost its entire load of propane, while another released some of its product and one crew member sustained minor inhalation injuries due to propane exposure.

“The investigation determined that rail within a joint failed catastrophically as the train passed over it, leading to the derailment of the 11th to 31st cars. The rail failure originated at a bolt hole crack within a joint in the south rail, which had propagated diagonally downward through the base of the rail likely due to one or more elevated wheel impacts that occurred prior to the arrival of the occurrence train,” the TSB said in a release on the incident.

TSB notes that despite regular inspections, the rail defect was not detected because the bolt hole crack and the rail base fracture were behind the joint bars which made visual detection difficult, especially in the winter months when snow covered the rail base. The cold temperature at the time of the accident also made the rail more susceptible to brittle failure.

TSB also found that CP training, procedures and guidelines were insufficient to protect the conductor from the hazards associated with the derailment and release of a large volume of propane while conducting the site assessment. TSB made note of a number of deficiencies that posed additional risk in this occurrence, particularly with respect to the lack of information available to crews and rail traffic controllers about the risk of ignition and the health hazards posed by products involved in a derailment.

“Although five of the six tank cars generally performed as intended, this derailment demonstrated that even a DOT-112 pressure tank car with improved design can be vulnerable to releasing product when exposed to high impact forces and sharp impact punctures,” said TSB.

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