On Thursday 23 June 2005, near Huntingdon, the overhead traction power lines came down during the evening peak on a very hot summer day. A number of trains were disabled without power. On board conditions deteriorated to such an extent that the passengers evacuated themselves from the train. The subsequent Network Rail inquiry established that a research project should be developed to identify incident control responses, staff learning requirements and ideas that could be developed to reduce the impact of future incidents when passengers were subject to prolonged extreme weather conditions.
The overall objective of the project was to establish the risks to passengers of detraining when the train air conditioning has switched off due to loss of traction current and the vehicle internal temperature has become uncomfortable. The RSSB contracted ESR Technology to carry out key parts of the research project such as assessments for on-train conditions, risk evaluation and passenger behaviour analysis.
The on-train condition assessment was undertaken on a small range of rolling stock by the use of the software tool VOLE (Ventilation Of Limited Enclosures). The output from this analysis by ESR Technology informed the industry of the air quality and temperature rise of a disabled train and at which point levels of passenger intolerability are reached. Assessments of the risk associated with detraining were developed and a comparison made with the risks of remaining on the train under extreme temperature conditions.
ESR Technology produced a guidance document for duty holders detailing the main findings from the research. It allows duty holders to compare their existing summer working procedures against these results enabling improvements to be made for the management of incident control responses relating to power outages on trains.