Effective Reliability, Availability, Maintainability (RAM) and Safety (S), Principles and Guidelines for Large Subsurface Metro and Main Line Projects

RAM requirements in large railway projects (such as Crossrail) are formed from a long time frame and a considerable suite of complex information. Projects investigate a variety of information which can include benchmarking other projects and operator’s systems performance. This includes risk evaluation and acceptance.

RAM begins by following guidance in BS EN 50126 [1] and its lifecycle related tasks. The complete life cycle can be seen in the Figure 1 which highlights the 5 early stages of RAM development. The first 5 tasks are usually with the DO to undertake with support from RAM engineers or specialist consultants. This is to develop and establish RAM requirements for design and implementation at stage 6.