Report on derailment with train 4842 at Flå on the Bergensbanen line on 25 June 2020
On Thursday 25 June 2020, a freight train from Green Cargo AB derailed when it caused buckling of the track at Flå on the Bergen Line. After several days of high temperatures and work on the track having caused weaker lateral stability, the circumstances were in place for buckling. The work was part of the “Ballast cleaning 2018–2020” project, performed by Baneservice AS, with Bane NOR SF responsible for day-to-day follow-up and management of the project. The investigation has uncovered that Bane NOR SF’s technical regulations are interpreted differently, and that the requirements concerning buckling are not specific enough.
In this investigation, the Norwegian Safety Investigation Authority (NSIA) has focused on buckling and how this phenomenon is addressed in regulations and requirements, as well as the inspection regime for work on the track.
Bane NOR SF has expertise in the risk of buckling, and both personnel and technical systems that monitor temperatures. This expertise and information were not effectively transferred to the ballast cleaning project. The investigation also shows that Bane NOR SF’s inspection regime was not sufficient to identify that the ballast cleaning project had interpreted the temperature limits in the technical regulations differently than what was intended.
Over the past seven years, the NSIA has investigated four similar derailing episodes caused by track buckling and submitted five safety recommendations. What these investigations have in common is work on the track, non-compliance with technical regulations, inadequate inspection procedures for track work, an unidentified risk of buckling, and a challenging interface between project work and day-to-day operations.
The NSIA considers that Bane NOR SF has not sufficiently learned from previous derailings caused by buckling.
In this investigation, the NSIA submits one safety recommendation to the effect that Bane NOR SF should clarify and ensure a correct understanding of the temperature requirement in the technical regulations.
Safety recommendation Rail no. 2021/16T
On Thursday 25 June 2020, GreenCargo AB’s train derailed when it caused buckling of the track at Flå on the Bergen Line. There had been several days of high temperatures, at the same time as ballast cleaning was taking place during the night, on assignment for Bane NOR SF. According to Bane NOR SF’s regulations, this type of activity must not be performed if the rail temperature exceeds 30 °C. The parties involved were under the impression that the temperature requirement only applied when work was actually being performed, without considering the expected daytime temperature.
The Norwegian Safety Investigation Authority recommends that the Norwegian Railway Authority ask Bane NOR SF to clarify and ensure a correct understanding of the temperature requirement in the technical regulations.
|Type of Transportation||Freight train|
|Type of occurrence||Derailment|
|Rolling Stock||Freight wagon|