Rail Accident Investigation Branch
Summary
At around 09:28 hrs on Friday 15 April 2022, a London Underground passenger train travelling at around 25 mph (40 km/h) struck and injured a track worker who was working as part of a planned patrol near Chalfont & Latimer station on the Metropolitan line of the London Underground network.
The track worker was working as part of a group of three, undertaking the role of second lookout, and had been provided by a recruitment agency for the days work. The patrol was planned to be undertaken during traffic hours when trains were running.
The accident happened because the track worker had moved from a place of safety and into the approaching trains path to get a better view of the track ahead, just as the train was about to pass her. She was walking with her back to the approaching train when she was struck and was not aware of the risk the train posed to her.
RAIBs investigation found that the track worker was not familiar with the exact location of the accident and that safety briefings provided to her on the day were not effective at giving her the information she needed to work safely.
Underlying factors to the accident were that London Undergrounds processes for managing track worker safety did not adequately control the risk to staff working on the line in traffic hours and that elements of the organisational culture at London Underground did not support effective management of track worker safety.
Although not relevant to the cause of the accident, RAIB observed that some designated places of safety on the Metropolitan line are sometimes obstructed, preventing them from being used as places of safety. RAIB also observed that the safety critical communications after the accident were effective, and that an accurate understanding of information was reached by all the parties involved.
Recommendations
RAIB has made four recommendations, all addressed to London Underground Limited. The first relates to a review of the assessment and control of the risks arising from working on the line during traffic hours. The second requires a review of the need to work on the track during traffic hours, with the aim of reducing such work. The third recommendation seeks improvements to safety assurance processes and safety reporting. The fourth recommendation aims to ensure that places of safety are fit for purpose.
RAIB has identified two learning points. The first relates to the importance of clear and effective safety briefings, and the second acknowledges the importance of effective safety critical communication in an emergency situation.