CASE STUDY: Assessment of the Risks of Adjacent Line Open Working

Risk Assessment Consultancy

Client: Network Rail

A Working Group set up by Network Rail formed to quantify the risks of adjacent line open (ALO) working has published a report detailing its output. As well as specialists from within Network Rail, the Working Group included industry partners, together with independent risk assessment support from Egerton Consulting and Liv Systems. ALO Crash To minimise the impact on an operational railway it is common practice to carry out some construction, maintenance and renewal activities whilst leaving adjacent lines open (ALO) to rail traffic. This is known as “working ALO”.

In 2011 there was growing interest within the rail industry in the risk profile of ALO working, and in particular the way in which activities were planned and how safe systems of work were being developed and deployed.  Site-based checks undertaken by Network Rail over several months in 2011/12 identified the need for ALO working practices to be improved to be confident that they were meeting legislative requirements and for the provision of a suitable and sufficient risk assessment as required by Regulation 3 of the Management of Health and Safety Regulations 1999.

As a background to the above checks, there had been two fatal collisions in Europe between trains and on track plant. It was therefore decided that the risks associated with the practice of working ALO should be formally assessed and their tolerability reviewed.

An industry Working Group was therefore formed to assess these risks and to develop a risk model, and subsequently the ALO Working Group was formed. The Working Group was sponsored by Network Rail with representatives from industry partners. In addition, Amanda Egerton (Egerton Consulting) and Chris Lowe (Liv Systems) were invited to join the Working Group to provide risk assessment and human factors expertise respectively, together with an independent perspective.

Using a combination of fault tree and event tree analyses Egerton Consulting facilitated the development of models to represent the probability of fouling an open line and the potential outcomes of such an occurrence. This led in April 2014 to the publication of a report (co-ordinated and co-authored by Egerton Consulting) which detailed the work that the Working Group had completed to quantify the risks of ALO working. The report considered the risks to train passengers and onboard staff associated with working ALO according to those procedures and practices that were in place in March 2012 and is available to interested parties from Safety Central at Network Rail.