Trains carrying crude oil from the Bakken oil fields in the United States are routinely misidentified, according to an industry analyst.

The Transportation Safety Board announced this week the crude oil carried in tankers that exploded in Lac-Mégantic, Que., in July was misidentified as a less volatile substance.

Donald Ross, the TSB’s lead investigator, said the inaccuracy in the labelling "explains in part why the crude ignited so quickly once the train cars were breached."

Bob van der Valk, the managing editor of the Bakken Oil Business Journal, said the misidentification is routine.

Dangerous goods

Flammable liquids included in Class 3, Flammable Liquids, are in one of the following packing groups:

  • Packing Group I, if they have an initial boiling point of 35 C or less at an absolute pressure of 101.3 kPa and any flash point;
  • Packing Group II, if they have an initial boiling point greater than 35 C at an absolute pressure of 101.3 kPa and a flash point less than 23 C; or
  • Packing Group III, if the criteria for inclusion in Packing Group I or II are not met.

Source: Transportation Safety Board of Canada

Van der Valk said Bakken crude oil is light, with a gravity of 36, which makes it far more flammable than most other crudes. He said it should be identified as diesel.

"Pretty close, you can actually run this in your engine without refining it, right out of the ground," he said.

The industry watcher said railway companies in the United States routinely fail to differentiate between Bakken crude and heavier, far less flammable, crude oils.

The Lac-Mégantic tragedy occurred when the 72-car, unmanned train rolled down an incline into the core of the town, left the tracks and exploded early in the morning on July 6. The blast and fires killed 47 people and destroyed several blocks neighbouring the train tracks.

The train, which belonged to Montreal, Maine & Atlantic railway, was carrying a shipment of crude oil destined for the Irving Oil Ltd. refinery in Saint John.

It's the responsibility of the importer, in this case Irving Oil, to ensure the description of the products are correct, the TSB's Ross said this week.

Irving Oil would not discuss the misidentification of the crude contained in the train.

"We continue to offer our full support to authorities as this tragedy is investigated. We are unable to offer further comment at this time," said Samantha Robinson, an official with Irving Oil Ltd., in an email with CBC News.

The TSB investigation is ongoing and the various failures of the tanker cars themselves are still being evaluated.