The Technical Specification for Interoperability (TSI) directive 2008/163/EC[1] ‘safety in rail- way tunnels’ defines a set of measures for various subsystems to deliver an optimal level of safety in tunnels. It aims to ‘permit free movement of trains complying with directives 96/48/EC (for high speed lines) and 2001/16/ec (for conventional lines) under harmonised safety conditions in railway tunnels on the trans European rail system’.






