Transport Canada proposes major safety changes to movement of dangerous goods

*The following regulatory news article is intended to be an overview of the report, legislation or proposal, and not a replacement for the actual guidance from the government. For the comprehensive data and all relevant information, please visit the linked source material within the article.

The Transportation of Dangerous Goods Regulations
The separation of dangerous goods from crews on trains — through buffer cars — is designed to give people more time to safely exit the train in case of an emergency or derailment. Photo Credit: Belish,

When it comes to the transportation of dangerous goods, Transport Canada is proposing to strengthen many existing rules, and introduce some new ones, as the department looks to align with U.S. and international regulations.

The regulatory update is widely a response to concerns raised by stakeholders, inspectors, and local authorities, particularly when it comes to enhancing buffer car rules for railway transport, and removing exemptions around the transport of anhydrous ammonia for farming.

Published in the December 9th edition of the Canada Gazette, Transport Canada states that the Transportation of Dangerous Goods Regulations under the authority of the Transportation of Dangerous Goods Act, 1992, “need to be updated to strengthen existing rules, clarify provisions, fix inconsistencies, and introduce new rules […].”

“Through these proposed changes to the Transportation of Dangerous Goods Regulations we want to strengthen transportation safety in Canada and reduce the risk of incidents involving dangerous goods,” announced Minister of Transport, Pablo Rodriguez, in a statement. “Our government’s top priority is always the safety of communities and employees throughout all aspects of transportation operations.”

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Buffer Cars

Transport Canada draws particular attention to issues surrounding buffer cars, a rule that has been actively applied in the U.S., but not Canada. Trains originating from the U.S. often have buffer cars placed on both ends of the train for the entire North American trip. The separation of dangerous goods from crews on train cars is designed to give people more time to safely exit the train in case of an emergency or derailment. They require a minimum of one buffer car between a railway vehicle carrying dangerous goods and an occupied railway vehicle for both unit trains. 

In Canada, mixed commodity freight trains do not require a buffer car if it is likely to negatively impact train dynamics. However, Transport Canada states that no criteria currently exist to specify situations that would have a negative impact on train dynamics, which results in inconsistent interpretations of the buffer car exemption.

“This misalignment between the U.S. and Canadian regulations means that train shipments which remain in Canada pose a higher-level safety risk for their crew than those that originate or are destined to the U.S.,” states Transport Canada’s proposed regulatory change. 

While not the case in Canada, U.S. regulations also require trains carrying loaded tank cars with the same commodity of dangerous goods to add buffer cars. 

Transport Canada is proposing to require at least one buffer car (i.e., empty or loaded railcar with non-dangerous goods) to be placed between an occupied locomotive for all trains (including unit trains) and rail vehicles carrying dangerous goods.

The department also aims to provide more detailed information about the potential impact of buffer cars on train dynamics. 

Transport Canada estimates that Canadian railway companies would incur a total cost of some $5.3 million to acquire additional buffer cars for the updated requirements. The department also estimates that a total of 53 buffer cars would be required by six railway companies.

Buffer car verification and placement on unit trains for domestic travels would be done during routine inspections, the department noted.

In Canada, there has been no report on, or investigation of accidents directly related to the absence of buffer cars in unit trains transporting dangerous goods domestically. 

Agricultural anhydrous ammonia exemption

Transport Canada acknowledges that farming practices have changed substantially over recent decades and suggests that its emergency plan exemption surrounding the transport of relatively small amounts of anhydrous ammonia has become outdated and creates a public safety risk. 

More than 30 years ago, the department exempted transporters from needing a shipping document and an emergency response assistance plan if the dangerous goods were being transported 100 kilometres or less, and in a tank that can hold 10,000 litres or less. 

Nowadays, multi-tank system configuration allows up to four tanks to be loaded on a single trailer for the transport of more than 10,000 litres of anhydrous ammonia without emergency response plan coverage on public roads.

Between 2002 and 2016, Transport Canada recorded 249 incidents involving anhydrous ammonia transported in nurse tanks, with a few reports of injuries due to chemical exposure, and in some cases, evacuation of residents nearby as a preventive measure. 

The department estimates that just 2% of anhydrous ammonia trips occur through an agri-retail location to a farm field by a farmer-owned nurse tank that is likely to not be covered by an emergency plan. The cost to a farmer to add such a plan can range from $1,000 to $5,000.

Transport Canada is proposing to change the current exemption from documentation and emergency plan requirements to apply only to its field application of anhydrous ammonia into the soil.

The department also proposes to remove the quantity limit of 10,000 litres of anhydrous ammonia from the existing exemption and clarify that only the use of either a single nurse tank or a twin nurse tank configuration would be permitted. 

The department also proposes to remove the conditions for the distance limit of 100 kilometres and require all agricultural anhydrous ammonia in transport in a quantity above 3,000 litres to be covered under an emergency response plan.

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