Having short overnight maintenance windows is a common challenge for metros globally. Overnight maintenance hours have reduced in 39% of COMET metros over the last five years and over half of them expected to face further pressure to increase service hours over the next five years. During overnight maintenance hours, metros typically spend less than 70% of the period on productive tasks (time-on-tools), which is normally between 2 and 3.5 hours each night.
The study reviews how metros measure performance regarding effectiveness and efficiency of overnight maintenance work, as well as barriers to overnight maintenance hours. Many metros have established procedures for identifying opportunities for innovations to address the barriers. The examples of innovations that have been used by metros to optimise different phases of overnight period include those relating to better advanced planning, changing maintenance philosophy, digitalisation of work orders, optimising staff travel and equipment deliveries, etc.