Why is Canada phasing out the DOT-111 rail cars early?

Come November, oil transported in Canada by rail will be carried in cars that are billed as sturdier and safer than their predecessors.

Federal Transport Minister Marc Garneau announced Monday that the DOT-111 cars, which were involved in the 2013 Lac-Mégantic disaster, will be phased out ahead of schedule.

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Garneau reiterated many times that the reason behind the accelerated timetable was a commitment to rail safety following the derailment and explosion that killed 47 people.

But Malcom Cairns, an Ottawa-based rail expert, pointed out that in the last 18 months, there has been a significant drop in the price of oil.

That led to shale producers halting production. Rail lines had been making up for the overworked pipelines, but that's no so much the case anymore. 

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"The amount of crude oil being moved by rail now has diminished quite considerably. As a consequence, obviously, that means that there need to be fewer tank cars actually moving oil at this time," he said.

John Byrne, vice chairman of the U.S.-based Railway Supply Institute's committee on tank cars, said the Canadian government is likely paying attention to the decline in volume, which would explain the timing.

"It makes sense now because there's little risk of affecting commerce," he said.

New cars supposed to better withstand heat, damage

The Transportation Safety Board issued a report detailing safety issues with the DOT-111 cars in early 2014, pointing out that it has been highlighting the vulnerability of the cars for more than 20 years.

American and Canadian authorities have both identified issues with the cars, including:

• The containers of the tank cars are typically made with 7/16-inch-thick steel, which makes them more vulnerable to damage than thicker steel.
• The legacy cars, generally built before 2010, don't all have thermal protection, which manages the transfer of heat into the tank in case of fire. The hotter it gets, the more likely the tanker will either explode or that the steel will melt, releasing the contents.
• On some DOT-111s, the heat shield, which protects each end of the car, only goes up halfway.
• The valves on top of the cars need stronger protection to make them less susceptible to damage if the car rolls over.

The federal government unveiled the rail cars they're hoping will become the new standard for transporting flammable liquids in May 2015.

Dubbed the TC-117 in Canada (DOT-117 in the U.S.), these cars have better thermal protection and are supposed to withstand puncture and other damage better than their predecessors, according to Byrne.

While the new cars represent a significant improvement over the DOT-111s, it's factors such as rail infrastructure and human error that cause derailments, not necessarily the type of cars transporting the goods, Byrne said. 

"None of the things they're doing with the tank car improvements will reduce derailments. They will reduce the severity of the derailments."

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