The Institution of Railway Signal Engineers (IRSE) celebrates its centenary in 2012, a remarkable achievement. The rail engineer interviewed Francis How, recently elected as President for the Centenary year, to discuss what had been achieved over the 100 years and the outlook for both the Institution and signalling into the future. The conversation ranged far and wide across issues of concern both to S&T engineers and the wider rail community.

The Institution was formally constituted in 1912 with a Memorandum of Association stating the purpose as:

– The advancement for the public benefit of the science and practice of railway signalling (which shall mean the whole of the apparatus, electrical, mechanical or otherwise, methods, regulations and principles whereby the movement of trains or other traffic is controlled) by the promotion of research, the collection and publication of educational material and the holding of conferences, seminars and meeting.
– The maintenance of high standards of practice and professional care amongst those working within the industry and the promotion of improved safety standards for the protection of the general public.

These two objectives have stood the test of time and are as relevant today as they were then. So, having survived two world wars and a number of signalling crises along the way, just what has the IRSE achieved for the industry and profession?


Not surprisingly, individual members of the IRSE have been at the forefront of many developments. However, as a corporate body, the IRSE has operated mainly in a responsive mode to technology advancement, providing wise counsel on various initiatives that have emerged down the years. There have been exceptions such as the Institution’s leading role in the development of the BR930 series relays.

When asked, the IRSE has given impartial advice on signalling, sometimes in the aftermath of an accident, where its independence and objectivity has been valued. The IRSE’s Signalling Philosophy Review in 2001 is still used as a reference work for matters relating to signalling principles and human factors in the design of signalling systems.

To help members and others with their professional development, the IRSE has produced many publications over the years. Initially, there were a series of “green booklets” on signalling principles and various types of signalling equipment. These have been followed by a number of text books ranging from the Introduction to Basic Signalling through to subjects such as ERTMS, Metro Signalling and Railway Telecommunications. These are probably the best source of information on UK S&T practice, although they also cover European and North American signalling systems.

The IRSE has an International Technical Committee, formed of leading experts in S&T technology, which meets regularly to consider signalling issues that are of concern to railways around the world. Several useful reports have been published by the ITC that can be viewed on the website. The application of ERTMS continues to be one of the main topics for discussion.

Above all else, the IRSE has enabled the meeting of minds on signalling matters across the globe, facilitating knowledge exchange and professional development through meetings, seminars and conferences as well as its publications. In earlier years it was perceived by many younger members as having an almost forbidding formality that gave an impression of the Institution being principally for the elder statesmen of the profession. Happily, over the years and in line with societal changes, this has been replaced by a much more inclusive style with the President and officials being far more approachable.

International dimension

The IRSE has always endeavoured to be the “voice of railway signalling and telecommunications” on the world stage. The present membership is nearly 5,000 – almost 50% of which have a non UK address. Separate sections exist in Australasia, South Africa, Hong Kong, North America, the Netherlands and, more recently, Singapore and Switzerland. Almost every country in the world with a railway of any significance has at least one IRSE member.

Communicating with and serving this widespread community is a challenge, and the IRSE’s governing Council works hard to ensure that its discussions take into account the need and interests of members around the world. Council meetings include participation via conferencing facilities with representatives outside the UK and the monthly publication “IRSE NEWS” regularly contains features and articles on subject matters from members who reside overseas.

Despite these efforts, it is arguable that the IRSE remains too UK orientated and Francis sees a possible solution by adopting a more federated model, allowing individual country sections to have greater autonomy and freedom to operate independently. He is also clear that the IRSE must remain a single worldwide body, the benefits of which are the envy of other professional engineering bodies.

Safety and accidents

Over the hundred years, signalling has rarely been an immediate and direct cause of railway accidents. Clapham was perhaps the worst of these and Francis considers that the changes made to signalling practise in the aftermath were absolutely right for the circumstances of the time. However, there has been a stagnation in the further evolution of good practice since then. The reluctance to move on and improve working processes to address matters other than just safety has been to the detriment of the UK railway.

When asked if safety can ever be overstated, the response from Francis was that signal engineers need to devote as much passion and energy to reliability as they do to safety, so to enhance the reputation of the profession as well as creating a better railway. In a rapidly changing world, signalling control systems have a great deal to offer in areas such as reducing traction energy consumption, reducing operating costs, increasing network capacity and reducing wear and tear on rolling stock and infrastructure. The need for signal engineers to apply effort to these challenges is paramount, but without ignoring safety.

Other than the few occasions of being a direct cause, signalling (or the lack of it) has been implicated in many other rail accidents, the principal ones being signaller error and signals passed at danger (SPAD). The accident at Quintinshill in 1915 cost 227 lives with another 245 injured and was entirely due to a signalman forgetting a train had been shunted to another line. The use of track circuits was accelerated and signaller reminder devices were introduced to prevent such lapses happening. SPADs have, however, continued to be a major cause of accidents with Harrow (1952) and Lewisham (1957) claiming 112 and 90 lives; more recently Southall (1997) and Ladbroke Grove (1999) cost 7 and 35 lives respectively.

The UK was slower than many other developed nations in introducing driver protection systems. The introduction of Automatic Warning Systems (AWS), forced in after Harrow, took many decades to complete and TPWS (Train Protection and Warning System) has been a relatively recent introduction. Whilst signal engineers were initially divided as to whether introducing TPWS (rather than full Automatic Train Protection) was the right decision, there is now widespread recognition that it has been highly effective and the problem of SPADs is much reduced as a consequence.

Many European countries adopted more sophisticated systems during the twentieth century, but these were of many different designs with resulting problems for cross border operation. The introduction of ERTMS will provide a Europe-wide ATP system but it is evident that it will take decades for its application to become widespread on existing networks.

Level crossings now present the biggest remaining risk to rail safety in terms of fatalities (including pedestrians struck by trains), although Great Britain has the best safety record of the European member states as measured by National Reference Values. Major rail accidents at level crossings are rare, although Lockington (1986) and Ufton Nervet (2004), with multiple fatalities, stand out as particularly serious. It is the road or footpath user who is most at risk. Most accidents occur at the lightly used minor road, pedestrian or farm crossings where controls are minimal, often a telephone at best. More could be done by using satellite positioning and navigation systems to warn crossing users that they are approaching a crossing and, possibly, whether or not a train is approaching.

Signalling principles and operating rules

Differing rules for operating railways have been devised around the world over many years with correspondingly different design requirements. Signalling is therefore, in some ways, a prisoner of history. This leads to the undesirable situation whereby new “standard” systems have to be customised or compromised to fit a particular country’s rules.

ERTMS is a prominent example where the functional and system specifications have had to incorporate options to meet the requirements of individual member states. There is a chance that achieving the seamless operational use of ERTMS across borders will not be as easy as originally intended.

Can the IRSE help to address this problem? Francis How thinks it could, but he observes that the IRSE is not as well known in mainland Europe as in the UK, making recognition of a potential contribution to bodies such as the European Railway Agency and the ERTMS Users Group more of a challenge.

Systems issues

A characteristic of modern signalling systems is that they will have as much equipment on the train as at the lineside. How does the IRSE handle this, particularly in the UK where there is a strong separation of ownership between track and train? This can be a sensitive issue as the train owners and operators are responsible for the integrity and operation of rolling stock and everything on it. Understandably, they want to take a ‘black box’ approach to train borne ERTMS equipment. However signalling is a system and needs to be specified, designed and managed with a systems approach.

Perhaps more significantly for the professional institutions, the interdependencies between signalling systems and other parts of the railway, including rolling stock, are becoming stronger. The growing complexity of software and data dependency also presents increasing challenges. Francis believes that much greater collaboration in the UK with the Institution of Mechanical Engineers Railway Division, the Institution of Railway Operators (IRO), the Institution of Engineering and Technology (IET) and INCOSE (International Council n Systems Engineering) is needed.

One step in the right direction could be to establish regular meetings at which the presidents of all institutions which can influence railway technology come together to debate issues of common concern and to seek greater synergy between their annual programmes of papers, meetings and events. Francis detects a certain willingness to do this in some quarters. Apart from the direct value to members, it would be a strong message to the wider rail technical community. Just how this would come about will require careful thought. The Railway Engineers Forum is already established as an informal liaison group between eight main rail orientated institutions. If it were to take a more prominent co-ordinating role, it would need the active support of the present institutions for such a move.

Competence and licensing

The Clapham accident (1985 – 35 dead, 500 injured) was a wakeup call to the signalling profession in the UK with much notice being taken by many other rail administrations as well. One of the outcomes was the formation of the IRSE Licensing scheme, which has become the most universally recognised competence standard for anyone working on safety critical signalling equipment. Since the scheme’s introduction in 1990, the categories of licence have been expanded to cover a broader range of both signalling and telecommunications activities, thus recognising the value in having a competence qualification for anyone working in the industry.

Whilst not appreciated by everyone, largely because of perceptions that it is overly bureaucratic and expensive, the IRSE Licensing Scheme continues to be the de-facto standard for S&T competence in the UK. Possession of a licence is valued as an independent qualification to practice in the signalling profession regardless of employer. Other engineering professions view the IRSE Scheme with a degree of envy and admiration.

Will the scheme survive in the longer term? Francis is ambivalent about that but counsels that the value of a scheme with independent UKAS accreditation of competence should not be under-estimated. The National Skills Academy for Railway Engineering (NSARE) may be the catalyst for transitioning the scheme into a wider rail competence management system under the umbrella of NSARE itself, taking the best that licensing has to offer and combining it with other methodologies that would suit all railway engineering professions

The future for the IRSE and signalling

Much of the underpinning technology for railway signalling and communications is changing more rapidly now than it has ever done before. Powerful computing capability, massive data storage and high speed communications present huge opportunities for railway control systems. Francis foresees a revolution in these areas over the coming years providing the profession is prepared to grasp the opportunity.

With that opportunity will come challenges, including that of system security. The dependence on systems outside the confines of the railway will continue to grow and it is now technically possible to manage a country’s railway traffic from anywhere in the world, operating over third party networks or the internet. If it were ever true that signalling systems were “closed off” from the outside world, certainly it is no longer so. The use of IP addressing is becoming the norm for many industrial applications and it is beginning to be applied to signalling. The idea of a set of points being called by IP addressing is not fanciful. Understanding and combating both malicious and unintentional disruption will be a challenge and although these could present safety risks, in practice attacks are more likely to be in the form of “denial of service”, causing widespread disruption to the operation of the railway.

In closing the discussion, Francis was asked whether the IRSE would exist in 2112. He would like to think so but says the more important thing is that the correct professional engineering institutions exist to serve the railway engineering and operations arena as a whole, thus providing a platform to support the development of the engineers and technicians that will be needed for the railway of the future. This does not necessarily mean preserving the IRSE, or any other Institution, in exactly the form they are in now.