Tunnel operation – safety assessment of existing vehicles
Older vehicles also need to satisfy fire-safety requirements, in particular if they travel through long trans-alpine tunnels in Switzerland. Evidence of their fire safety is provided through documented assessment of fire risks. TÜV SÜD Rail has been commissioned by Schweizerische Bundesbahn (SBB), Switzerland's national railway company, to assess the fire safety of its existing rolling stock made up of various types of vehicles.
In line with SBB's safety concept, the company's vehicle fleet undergoes regular assessment of its fire-safety risks in line with the currently valid and applicable legal and normative requirements. As existing vehicles generally comply with the standards applicable at the time when they were first put into operation, many of today's technical requirements may not have been realized. However, this is not necessarily associated with a safety deficit as can be proved through expert assessment of the residual risk.
SBB commissioned TÜV SÜD Rail to assess the fire safety of its existing vehicle fleet comprising the vehicle types FLIRT, Domino, DTZ and HVZ (both suburban railway Zurich) and the RE 420 locomotive. The project covers over 500 vehicles of different types and equipment.
Fire-safety assessment is based on a generic risk analysis associated with an 'as-is' analysis of the current technical equipment and the vehicle operation realised. For risk analysis, the experts determined the specific fire risks of the vehicle type and/or vehicle fleet under assessment and set it in relation to the relevant objective of “personal safety”.
In parallel, the fire-safety experts compared the fire-safety requirements outlined in the applicable standards and documentation as generally accepted rules of technology and included them in the assessment. Based on these assessments, the rail professionals then identified measures not linked to a specific technology (technical / operational / organisational) to reduce the potential fire risk in connection with its potential consequences to a safety level “equivalent to that defined in the generally accepted rules of technology”.
Using these findings, SBB can develop and evaluate possible measures from the operator's perspective and decide on theirimplementation in line with the limits of acceptance of residual risk that the company defined for itself. At present, TÜV SÜD Rail's experts are supporting the ongoing modernization concept for the IC 2000 double decker fleet with around 340 rail cars, providing continuous testing services during design and development. Final documented assessment of the vehicles will be one of the criteria for the Swiss Federal Office of Transport (FOT) to approve the rail vehicles for returning to service throughout the SBB network including the long AlpTransit tunnel.
Given the efficient functional collaboration, there is nothing to stand in the way for further cooperation and vehicle-assessment projects of the two business partners, TÜV SÜD Rail and SBB, in the future.