Informa Markets

Author Bio ▼

Safety and Health Practitioner (SHP) is first for independent health and safety news.
March 29, 2010

Get the SHP newsletter

Daily health and safety news, job alerts and resources

Railway tracks safety and risk controls

Between 1999 and 2008 there were 28 track-worker fatalities, 22 as a result of being struck by a train. In light of this, David Shirres considers the nature and effectiveness of risk controls for track work and highlights issues that he believes need to be addressed to reduce the risks from work in possessions and improve productivity.

Work on the track is undertaken either in a possession,2 or on the open line, subject to safety arrangements set up by the controller of site safety (COSS). Despite ten years of national track-safety initiatives, little progress is evident, owing to the slow pace of improvements. For example, the Rail Accident Investigation Branch’s report on the collision between a train and trolley at Kentish Town in October 20093 notes that its recommendations from a similar incident at Acton West in June 20084 have yet to be implemented.

There is no doubt that Network Rail is committed to the reduction of accidents within possessions – its Strategic Business Plan requires improvements in possession efficiency as part of the seven-day railway objective.5 So why has there been so little change in possessions management?

One reason is perhaps an industry culture focused on rule compliance. Although this is a great strength, it can also lead to a blame culture that does not allow for genuine errors made by competent individuals who have to work in poor conditions. As a result, low priority is given to supporting processes, such as the provision of information.

Another reason is that, within the rail industry, the responsibility for production of track-safety rules is not in accordance with legislative requirements. Network Rail, as the employer of all who work in possessions, has a duty under the Management of Health and Safety at Work Regulations to provide appropriate instructions. However, possession rules are produced by the Rail Safety and Standards Board (RSSB), as they are deemed to be Railway Group Standards and so are produced in accordance with the Railway Group Standards Code.6

This defines how relevant standards committees are responsible for changes to standards, and specifies a consultation process, which requires the committees to take account of the views of myriad stakeholders. This is why it can take years to change railway rules.
Possession rules are produced by a committee that is primarily concerned with rules for the operation of trains on the open line. This committee comprises 19 individuals, only three of whom work for Network Rail. So, because the rules are produced by RSSB, with Network Rail responsible for supporting processes, there is a lack of focus and accountability for the specification of possession risk controls.

Possession safety arrangements
Within possessions, there are three main areas of risk:

  • Movements of trains and on-track plant (OTP) – The rail industry’s Rule Book requirements are, in effect, a structured Permit-to-Work system that gives the COSS the authority to start work when the person in charge of possession (PICOP) and then the engineering supervisor (ES) have ensured that there is no risk from train movements.
  • Isolation of electrical supplies – If the work requires an isolation of overhead or third-rail power supplies, the COSS must have a permit before work can start.
  • Engineering work – Risks associated with the actual work are the responsibility of Network Rail or its contractors, and are outside the scope of possession rules. Hence, the COSS is not necessarily responsible for the safety of engineering work.

Thus, possession management communications are unnecessarily complicated. Consider the following issues:

Clarity of rules and terminology
Rules for work in possessions are specified in certain modules in the Rule Book. Although these modules contain instructions that are intended to be applicable to specific roles, this does not apply to possessions in which, for example, a COSS must understand several modules. That track safety arrangements are defined in separate Rule Book modules is, perhaps, symptomatic of the lack of a holistic approach to track safety.

In addition, some of the terminology used in the Rule Book is misleading – for example:

  • Person in charge of possession (PICOP) – The PICOP takes possession of the line from the signaller and authorises worksites to be set up but has no authority over the work that takes place within possession worksites;
  • Possession worksite – This is the section of line controlled by the engineering supervisor. Work generally does not take place throughout the possession worksite and there may be several COSS sites of work within it.
  • Engineering supervisor (ES) – The ES controls train movements within the possession worksite and is not necessarily either an engineer or a supervisor;
  • Controller of site safety (COSS) – The COSS only controls site safety in respect of train movements and isolations, and does not control the actual work;
  • COSS site of work – This is an undefined area controlled by the COSS and is not necessarily the same as the possession worksite (an important distinction).

Ideally, Rule Book modules should be restructured around possession work. But because of the length of time it takes to change railway rules a better way of addressing this issue would be for Network Rail (as employer of all those who work in possessions) to produce a single guide to possession safety, which refers to all relevant rules and clarifies issues that are currently unclear.

Situational awareness
It is essential that all concerned understand all aspects of the possession relating to their work situation. This requires both local knowledge of the area and an understanding of the limits of possession, possession worksite, site of work, and isolation.
Although maintenance personnel will have an intimate knowledge of their area, project contractors work throughout the UK and cannot be expected to have such detailed local knowledge. Other than at complex track locations, this is a risk that can be controlled if personnel are provided with diagrams showing the required information, and are trained how to use them. However, Network Rail does not have a process7 to provide its staff and contractors with the required information to produce such diagrams (e.g. mileages of signals and points). This would seem to be a breach of both the CDM and Management of Health and Safety at Work Regulations.

In a possession, the location of various limits and access points are defined in different ways – such as by signal/points numbers, or mileage – so the only way of presenting all limits in an understandable manner is in a diagram (the RAIB report into the Acton incident4 recommends the use of diagrams). Thus, in complex possessions, diagrams must be produced that can be used to brief all concerned. Network Rail should provide the necessary information for these diagrams.

Role of the COSS
The function of the COSS, both in possessions and on the open line, is to set up a safe system of work to protect the work group. On the open line the COSS has an active and demanding role in establishing one of 11 different safe systems of work by, for example, placing lookouts, or arranging with the signaller for the line to be temporarily closed.

In a possession with all lines blocked, the safe system of work has, in effect, already been established and the role of the COSS is to authorise work to start once authority has been received from the engineering supervisor. To be competent, a COSS must be able to fulfil the full range of COSS duties, both on the open line and within a possession. However, around a third of COSSs work only in all-lines-blocked possessions,8 so if such COSSs occasionally work on an open line, there is a safety risk. There is therefore a need for a simplified all-lines-blocked possession COSS competency.

Possession rules do not give the COSS any safety responsibilities for the actual work, as this is controlled by a site supervisor. Although the COSS and site supervisor is generally the same person, it is not feasible for all site supervisors to obtain and maintain the full COSS competency. As a result, site safety may end up being controlled by two different people with different roles. Again, this unnecessary risk could be eliminated if there was a simplified all-lines-blocked possession COSS competency, which could then be compulsory for all site supervisors in possessions.

OTP movements
Perhaps the most significant change in possession working since the break-up of British Rail has been the increase in the use of on-track plant (OTP). This is governed by the rules associated with train movements but, unlike engineering trains, OTP enters the possession at an OTP access point, where it is placed on the track. As OTP access is an integral part of the engineering work, the distance between the access point and site of work governs the length of the possession worksite, which may end up being miles long as a result.

Movement issues associated with OTP in possession worksites are:

  • The allowable speed of OTP movements within possession worksites is unclear. Although OTP must move at walking pace at the COSS site of work, there is no such requirement in the remainder of the possession worksite. Possession rules specify a default speed of walking pace in the possession worksite but offer no guidance on when walking pace can be exceeded. As a result, OTP generally moves at walking pace throughout the worksite. With OTP access points being miles apart, typically it can take an hour for the return journey from the access point to the worksite.
  • When engineering trains pass through the possession worksite all OTP must be off-tracked before the engineering supervisor authorises the move. As there is also no defined process to record this, the engineering supervisor is often expected to memorise which machines have been off-tracked.
  • Possession rules require the ES to authorise each movement in a possession worksite. As there are likely to be frequent OTP movements along a particular section of track, it is not feasible for the engineering supervisor to authorise all of them so, in practice, machine controllers control OTP moves over a section of track. Possession rules do not address this issue.
  • OTP moves through points in the wrong position are expensive and happen quite often. One reason for this is the lack of a defined process to set a route within a possession. In the case of the open line, the Rule Book does specify a route-setting process in the event of a signal failure; applying this to possessions would significantly reduce such incidents. This would require diagrams with specified point numbers and names of each line, i.e. the same information available to the signaller.

Because enhancement of the possession rules to address these issues could take some years, a more immediate solution would be for Network Rail to address them in the guide to possession safety suggested earlier.

PICOPs and engineering supervisors
Control of train movements on the line under possession is handed over from the signaller to the PICOP and then to the engineering supervisor. The signaller has the advantage of not only interlocking9 but also access to the signalling panel, which shows all relevant information (e.g. points and signal numbers, names of lines, etc).
In contrast, many possessions are managed from a van by PICOPs and engineering supervisors, who have to rely on their memory and local knowledge. Although this may be appropriate for simple possessions managed by those who know the location, it is difficult to see how complex possessions can be safely controlled unless PICOPs and engineering supervisors are given suitable facilities.

Within the industry there is a view that possession risk is minimised by keeping possession worksites to a short length, with only one contractor in each one. However, this could significantly reduce possession productivity without addressing the need to provide those who manage possessions with the required facilities to reduce risk from reliance on human memory. Network Rail should therefore mandate a standard on the provision of such facilities.

Power-supply isolation
For most engineering work on electrified lines traction power supplies must be isolated and earthed before work can commence. The isolation limits for the overhead traction supply (normally energised at 25,000 volts) are defined by mast numbers, with no physical indication of isolation limits on the ground. When, for practical reasons, it is not possible to isolate the entire possession, or possession worksite it is particularly important that all concerned are aware of isolation limits. Again, a possession diagram would provide greater clarification of these limits.

If work requires an isolation, possession rules require a Permit to Work to be issued to each COSS before work can commence. Where there are many COSSs in a possession worksite, it would be appropriate to issue the permit to the engineering supervisor, as COSSs cannot start work without the engineering supervisor’s authority.

Access points
All personnel, equipment and on-track plant gain access to the site of work by railway access points, which may be some miles from the site of work, making the movement of personnel along the railway line both a safety and productivity issue. A simple and cost-effective improvement would be for access points to be specified at the outline design stage of rail projects. Currently, however, Network Rail has no standard requiring project designers to consider access points.

Do rules keep track workers safe? I would say “yes, but. . .” In general, possession rules do control the risk to track workers, but there are some risks that are not adequately addressed by current rules, which are themselves presented in a manner that is not easily understood.

The issues I have raised in this article need to be addressed to reduce the risks associated with possession work. However, to implement any solutions effectively lessons must first be learnt from the lack of progress on possession management improvements to date. Perhaps the most important lesson is that Network Rail, as the responsible employer, should take ownership of both track-safety rules and supporting processes.

Unless this is done it is likely that the risk to track workers will remain at the upper limit of tolerability, and possession rules will continue to reduce productivity in possession worksites unnecessarily. This is a situation that should not be allowed to continue.

Summary of suggestions

  • Network Rail should take ownership of both track-safety rules and supporting processes
  • There should be clear accountability for the specification of possession risk controls
  • Rules and terminology should be clarified in a single guide to possession safety
  • There should be a robust system for providing those working in possessions with all the information they need for possession planning, presented in a clear and easily understandable format
  • To avoid situations in which a site is controlled by different people with different competencies there is a need for a simplified all-lines-blocked possession COSS competency
  • PICOPs and engineering supervisors must be provided with standard facilities from which to manage possessions – e.g. a proper office, with whiteboards, charts and diagrams, etc.
  • Railway access points should be specified at the project design stage


SHP contacted Network Rail to contribute to this article and received the following response:

Network Rail is committed to improving its safety performance. Since taking over from Railtrack we have achieved a significant improvement in our Accident Frequency Rate. The level of performance compares very favourably to comparative industries where similar activities are carried out, in terms of construction and maintenance. The safety performance of the rail network and assets over which trains operate is now better than most of our European counterparts. Rail travel in Great Britain is one of the safest modes of transport.

This has not happened by chance and has required an obsessive focus on risk, working collaboratively with industry stakeholders and partners, including Train Operating Companies, major contractors, suppliers, and our safety regulator, the Office of Rail Regulation.
The issues raised in the article are known to Network Rail and are being addressed as part of our safety improvement programme. Issues pertaining to the operation of on-track plant, improvements to the planning process for developing safe systems of work, and the competence of those people responsible for planning work and controlling safety at work sites all feature in the programme. Progress is regularly reviewed by our executive and with the Office of Rail Regulation.

It is also worth noting that we are looking at new technology and how this can be applied in reducing the need for human intervention in the inspection and maintenance of our assets, working on the simple principle that if you reduce the need for people to go on to the track you will inevitably reduce the number of times that people come into contact with trains, or heavy machinery.

To support this kind of change we work closely with the RSSB in developing Rail Group Standards and have developed processes for reviewing and amending standards – both specific to the Railway Group and Network Rail – that maintain rigour while reducing bureaucracy.

Safety performance on Britain’s railways is now consistently better than at any time in recorded history. That said, three recent fatalities involving two employees of our contractors and one of our own Network Rail team act as a salutary reminder of the need to constantly revisit everything that we do and how we do it, with the aim of keeping everyone who works and travels on our network safe.


  1. Rail Safety Standards Board Safety Performance Report 2008 – chart 43
  2. Possession is the closure of a section of a route to normal train operations to enable engineers to work on the rail infrastructure
  3. bulletins_2010/bulletin_02_2010.cfm
  4. investigation_reports/reports_2009/report152009.cfm
  5. StrategicBusinessPlan/Update/
  6. Move towards a seven day railway –
  7. As at November 2009, Network Rail’s Geographical Information System (GIS) did not include the information required for possession planning (e.g. access points, location of signals and points numbers)
  8. According to a survey undertaken by the author
  9. Signalling interlocking prevents conflicting movements of trains and ensures points are in the right position

About the author
David Shirres recently retired after 37 years in the rail industry and is a member of the IOSH Rail Group.


The Safety Conversation Podcast: Listen now!

The Safety Conversation with SHP (previously the Safety and Health Podcast) aims to bring you the latest news, insights and legislation updates in the form of interviews, discussions and panel debates from leading figures within the profession.

Find us on Apple Podcasts, Spotify and Google Podcasts, subscribe and join the conversation today!

Related Topics

Notify of

Inline Feedbacks
View all comments