The Transportation Safety Board Report R15H0005 says a freight train derailment in northern Ontario was caused by the complete failure of a previously cracked rail.
On Jan. 13, 2016 the Canadian Pacific train with 31 cars was travelling about 34 kilometres east of Nipigon. This train included seven dangerous goods tank cars loaded with propane.
The investigation revealed that a cracked rail gave way completely as the train passed over it, derailing the cars.
Despite regular inspections the crack went unnoticed; because it was located behind joint bars, making it difficult to spot at a time when the track base was covered in snow.
The TSB says CP’s safety procedures were lacking in the incident. One crew member sustained minor inhalation injuries. “The decision on whether emergency medical services were required was left to the conductor, who had already sustained exposure to the propane and was working in a stressful situation. Given that propane inhalation is a serious health risk that can also affect cognitive abilities, the conductor was not in an objective position to be able to make this determination at that time. Despite the conductor’s repeated exposure to the propane, medical assistance was not specifically requested until the locomotive engineer intervened about 2 hours later.” the board wrote in its report. “In this occurrence, 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 performing a detailed site assessment.”
The report in its entirety can be found here.