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Findings from TSB investigation R17W0267 – December 2017 employee fatality in Melville, Saskatchewan

Investigations conducted by the Transportation Safety Board of Canada (TSB) are complex since an accident rarely results from a single cause. In the case of the Melville, Saskatchewan, accident on 22 December 2017 several factors led to the uncontrolled movement and employee fatality. The 9 findings below detail the causes and contributing factors that led to this occurrence. Additionally during the course of the investigation, the TSB also made 7 findings as to risk and 9 other findings.

Findings as to causes and contributing factors

These are conditions, acts or safety deficiencies that were found to have caused or contributed to this occurrence.

  1. The accident occurred when 3 open-top hopper cars loaded with ballast were kicked up an ascending grade on the MR-lead track, stalled, rolled back, and collided with the lead car of the assignment, empty car PLCX 21492, which was foul of the lead track.
  2. While attempting to stop the uncontrolled cars by applying the hand brake on CN 302412, the foreman became pinned between PLCX 21492 and CN 302412, receiving fatal injuries.
  3. When the foreman applied the hand brake, the welds securing the bell-crank bracket to the underside of the B-end sill of CN 302412 failed, and the bell crank and the bracket separated from the car, rendering the hand brake ineffective.
  4. Because the braking efficiency of the hand brake was compromised, the uncontrolled movement did not stop or slow, which reduced the opportunity and time for the foreman to safely egress.
  5. Regular pre-departure inspections, certified car inspections (CCI), and single-car air-brake tests did not detect the cracked bell-crank bracket welds prior to failure.
  6. The assignment foreman’s plan to kick the 3 open-top hopper cars loaded with ballast into track MR13 on an ascending grade was inadequate because it did not take into consideration the amount of room required to receive all 3 cars, the momentum required for the cars to reach the track, and the need to monitor the movement to ensure that the speed was adequate for the cars to reach their intended destination.
  7. The foreman’s limited experience in operating a remote-controlled locomotive system during switching operations likely contributed to the development of an inadequate plan and the attempt to kick the 3 cars at too slow a speed in an area of known ascending grade.
  8. There was insufficient communication between the crew members, contributing to the inadequate plan.
  9. The crew members’ reserve, inexperience in working together, and relative inexperience in their roles on the day of the accident likely contributed to their infrequent communication during their shift.

Findings as to risk

These are conditions, unsafe acts or safety deficiencies that were found not to be a factor in this occurrence but could have adverse consequences in future occurrences.

  1. If the securement of bell-crank brackets and bell cranks, which are critical to the safe operation of hand brakes, does not require the same mounting and inspection criteria as safety appliances, a defective bell crank can compromise hand-brake effectiveness, which increases the risk of accidents.
  2. If freight cars with high-mounted hand brakes and end platforms remain in service, hand-brake operation during an emergency might be delayed and employee emergency egress made more difficult, which increases the risk of employee injury.
  3. If crew members do not receive enhanced crew resource management training to develop skills in crew coordination and communication, there is an increased risk that inadequate crew communication will lead to unsafe operations.
  4. If the role of yard foreman has no requirements related to their experience with the tasks involved, the scheduling system used to fill the positions can result in inexperienced employees being put in charge of unfamiliar tasks, increasing the risk of error.
  5. If the Railway Employee Qualification Standards Regulations are not updated, effective regulatory oversight and enforcement of safety-critical positions will be compromised, increasing the risk of unsafe train operations.
  6. If a railway’s safety management system does not include comprehensive close-call reporting of systemic operational issues that do not result in adverse consequences, effective mitigation strategies will not be implemented, which increases the risk that similar or more serious accidents will continue to occur.
  7. If effective strategies are not taken to improve safety while switching without air, uncontrolled movements will continue to occur, increasing the risk of adverse outcomes.

Other findings

These items could enhance safety, resolve an issue of controversy, or provide a data point for future safety studies.

  1. Prior to the collision, the hand brake wheel on CN 302412 had been turned beyond what was required to fully apply the hand brake.
  2. Once the hand brake was fully applied, a fully effective hand brake on car CN 302412 could have stopped the uncontrolled movement within the available distance.
  3. Since a detached bell-crank bracket and bell crank would hang low and be easily identifiable to inspectors and operating employees, the bell-crank bracket and bell crank were probably in place at the time of the most recent certified car inspection  of CN 302412 and immediately before the accident.
  4. Heavy corrosion on the fracture surfaces of the welds that secured the bell-crank bracket to the underside of the B-end sill of CN 302412 indicated that the cracks had likely been present (but undetected) for an extended period of time, including during the most recent certified car inspection.
  5. A detailed inspection of the bell-crank bracket welds is not required during a certified car inspection  and any cracks in the welded securement would have been difficult to identify due to the location of the welds.
  6. The Canadian National Railway Company initiated a detailed inspection of its open-top hopper fleet and subsequently identified that 63 of 857 cars had a total of 71 defects, which included 5 bell-crank bracket defects.
  7. Since the assignment was already stopped on the MR-lead track, it is likely that the collision activated the emergency air-brake application.
  8. While the Canadian National Railway Company’s local corrective measures focused on individual employee education, clarification of instructions, and increased monitoring, these corrective measures did not fully address the challenges associated with switching on the ascending grade of the MR-lead track.
  9. Despite safety action taken by Transport Canada and the railway industry, the desired outcome of significantly reducing the number of uncontrolled movements has not yet been achieved.