Canada Road & Rail Transport - Coupling Railway Vehicles

Coupling speeds for railway vehicles carrying dangerous goods are regulated according the outdoor air temperature. If a railway vehicle contains dangerous goods that require placarding, that railway vehicle must not be coupled with another railway vehicle at a relative coupling speed greater than 9.6 kilometres per hour. However, when the ambient temperature is above -25°C, a railway vehicle not yet connected to other railway vehicles and moving under its own momentum may be coupled at a relative coupling speed less than or equal to 12 kilometres per hour.

If a person couples a tank car that contains dangerous goods for which a placard is required to be displayed with another railway vehicle, and certain conditions detailed in the table shown in Part 10, Section 10.7 (relating to combined coupling mass, ambient temperature, and relative coupling speed) apply, the person must do both of the following:

• Visually inspect the underframe assembly and coupling and cushioning components of the tank car to ensure their integrity before the tank car is moved more than 2 kilometres from the place where the coupling occurred.
• Report, in writing, to the owner of the tank car within 10 days after the coupling and include a copy of Part 10, Section 10.7 of the TDG Regulations and information about any damage that compromises the integrity of the underframe assembly or draft gear of the tank car discovered in the course of the inspection.

The owner of a tank car who receives the report must not use the tank car or permit the tank car to be used to transport dangerous goods, other than the dangerous goods that were contained in the tank car at the time of the coupling until the following inspections have been made:

• A visual inspection
• A structural integrity inspection
• A stub sill inspection (for a tank car equipped with a stub sill)

The foregoing information about coupling railway vehicles does not apply if either the tank car or the other railway vehicle that was coupled has the following characteristics:

• Is equipped with a cushioning device designed for a displacement of 15 centimetres or more in compression
• Is capable of limiting the maximum coupler force to 453,600 kilograms when impacted at 16.1 kilometres per hour by a railway vehicle having a gross mass of 99,792 kilograms

To learn more about Transporting Dangerous Goods in Canada visit our Transporting Dangerous Good by Road & Rail Online Training web page.