Canada’s Transportation Safety Board has issued a pair of rail safety advisories aimed at improving rail safety and preventing uncontrolled train movements on mountain grades.
The advisories were issued to Transport Canada on April 11 and stem from TSB’s investigation of a deadly train derailment earlier this year near Field, B.C., that killed three Canadian Pacific train crew members.
According to a news release dated April 18, the TSB advised Transport Canada:
• to ensure that effective safety procedures, including the application of hand brakes, are used in all instances where trains stopped in emergency on both “heavy grades” and “mountain grades”;
• to review the efficacy of air brake system inspection and maintenance procedures for grain hopper cars used in unit train operations at CP and other railways as necessary, to ensure that unit grain trains can be operated safely at all times.
On Feb. 4, a loaded unit train consisting of 112 grain cars and three locomotives was brought to an emergency stop at Partridge, B.C., using an emergency air brake application.
The train was en route to Vancouver. The track grade at the location was 2.2 percent.
After consulting with a supervisor, the train’s crew set retainer valves to the high pressure position on 75 percent of the cars, or 84 hoppers. According to TSB investigators, no hand brakes were applied.
After a period of about two hours and 45 minutes, a relief crew arrived at Partridge to replace the previous train crew, which had reached the end of its shift.
About 10 minutes later, the train began to move on its own.
The relief train crew had not yet recovered the air brake pressure from the emergency brake application, the TSB said.
Crew members were in the process of securing the train to facilitate the safe release and recharge of the air brakes.
The train gradually accelerated to a speed in excess of the maximum track speed, before derailing.
A total of 99 cars and two locomotives left the tracks between the Upper Spiral Tunnel and Lower Spiral Tunnel near Field.
The crew members on board, including locomotive engineer Andrew Dockrell, conductor Dylan Paradis and trainee Daniel Waldenberger-Bulmer were killed in the derailment.
The temperature at the time of the accident was −28 C.
In its investigation, the TSB determined that before arriving at Partridge, crew members had been unable to keep the train at or below the maximum authorized speed of 15 miles per hour (24 km-h) despite using “a progressive application of air brakes and dynamic brakes.”
The train eventually reached a speed of 23 mph (37 km-h) before it was stopped at Partridge using emergency air brakes.
In its advisory, the TSB said any train descending a heavy or mountain grade that attains a speed of five mph above the maximum permissible speed is considered an uncontrolled movement.
Trains that are stopped with emergency air brakes on a grade of 1.8 percent or greater should immediately have a sufficient number of hand brakes applied while the train’s air brake system is recharged, TSB added.
“A properly functioning air brake system is of the utmost importance in mountain territory from a safety standpoint,” wrote Kirby Jang, director of rail investigations at the TSB in the second advisory.
“For unit bulk commodity trains operating on Field Hill, CP has implemented a number of risk mitigation measures. With warmer ambient temperatures in the spring, this seasonal relief will help restore air brake efficiency,” Jang continued.
“However, given the potential consequences when uncontrolled movements occur, particularly in mountain territory, Transport Canada may wish to review the efficacy of the inspection and maintenance procedures for grain hopper cars used in CP’s unit grain train operations (and for other railways as applicable), and ensure that these cars can be operated safely at all times.”