To ask the Secretary of State for Transport, pursuant to the Answer of 14 January 2026 to Question 102105 on Network Rail: Assets, what assessment she has made of the effectiveness of Network Rail’s calculation of the Composite Sustainability index for ea
The methodology for the composite sustainability index (CSI) calculations is developed by Network Rail and is recognised by the regulator, the Office of Rail and Road, as being a reliable and effective means to monitor the changing remaining life of railw...
Network Rail: Assets