The Rail Accident Investigation Branch (RAIB) has published its findings on a significant near-miss incident in Bookham Tunnel, Surrey, which saw a passenger train pass dangerously close to track workers. The event, which took place on 29 April 2025, involved three Network Rail employees who were undertaking duties within the tunnel when a train approached at approximately 33 mph. The workers were forced to move into refuges or press against the tunnel wall as the train passed.
RAIB's investigation concluded that the primary cause of the near miss was the track workers operating in a different location to the one that had been designated as blocked to trains. This critical error stemmed from the safe work pack, a crucial document detailing safety arrangements for the task, incorrectly listing line blockage details for the nearby Mickleham Tunnel instead of Bookham Tunnel. This mistake, introduced during the initial planning stages, went undetected despite multiple checks throughout the safety process.
The report identified two key underlying factors contributing to the oversight. Firstly, Network Rail's lack of a specific procedure for managing the transfer of information between its asset management systems and the system used to generate safe work packs allowed the initial error to be introduced. Secondly, the RAIB found that certain steps within Network Rail's existing process for producing these safe work packs were either not consistently carried out or were not implemented effectively.
In response to its findings, RAIB has issued three recommendations directed at Network Rail. The first aims to mitigate the risk of errors when compiling information from various systems into safe work packs. The second urges Network Rail to enhance the implementation of its processes governing work on or near operational railway lines. The third recommendation advises Network Rail to improve its assurance activities by making better use of the data provided by its safe system of work planning software.
Andrew Hall, the Chief Inspector of Rail Accidents, commented on the findings, stressing the heightened reliance on accurate information in modern railway safety. He stated, "Our investigation into this near miss illustrates how safety is now heavily dependent on every worker having an accurate understanding of which lines are blocked, the timing of the block and where the safe working boundaries lie." He further warned that a series of near misses can ultimately lead to a tragic outcome, referencing a recent fatal incident in Hertfordshire as a stark reminder of the urgency of ongoing safety improvements.