Big sporting events mean big crowds and the need for mass transportation systems.  In many cities this need has recently been met by retrospectively fitting light rail and tram systems into existing and older city infrastructure.  As you travel on these electric rail systems you may wonder what safety challenges they face and how they are managed.  This is actually an important stray current corrosion concern because it is inevitable that operation of these direct current (DC) light rail and metro systems will generate some stray or leakage current. In most systems, the electric current required to run the vehicles returns to the power source via the running rails. It is not possible to fully insulate the rails from the ground, which meant some current will leak or stray into the ground.

In urban areas, where these transit systems typically operate, there are buried metallic infrastructure such as gas pipelines and power cables sheaths and the stray current from the rails may interact with these utility services. Stray current can accelerate the corrosion rate of unprotected metal surfaces and lead to early failure, increasing repair costs, increased leakage rates and possible safety and environmental risks.

There is also the possibility of corrosion of the transit system rails, buried trackside equipment and structures such as bridges or tunnels.

It should be noted that only metal surfaces are affected and plastic pipes or cables with plastic outer sheaths are immune – a positive for many modern digital cabling services and newer water systems.

Getting stray current wrong costs time and money, devalues assets and can become safety-critical

However, if good practice is followed, interference and accelerated corrosion can be avoided. Transit system operators can effectively manage stray current by controlling stray current at source. This may be achieved by maintaining track bonding to provide a low resistance path for the return current – this encourages more current to remain in the rails by providing an attractive return route for the current. In addition, maintaining effective rail insulation helps to minimise losses by acting as a barrier. However, in wet conditions, the rail insulation tends to be less effective and stray current typically increases. It is therefore important to ensure drainage is effective, to avoid pooling of water and allow rainfall to run away efficiently.

Stray current is always an on-going issue and levels may increase over the years due to degrading rail insulation or other system faults. Because of this risk, regular monitoring is carried out to check the level of interference and the impact of any stray current. Criteria given in standards allow interference levels to be assessed and actions prioritised.

Monitoring typically includes the routine collection of stray current performance data from monitoring locations on the transit system and on a mix of water, gas and power utility assets. Evaluations are also carried out as part of repair work operations to ensure changes do not inadvertently introduce a bigger risk.

On most systems, to ensure that stray current is managed successfully and any issues are satisfactorily resolved, technical groups are arranged including the transit owner and operator and affected third parties, such as utility companies.

Travelling to the big match conveniently on mass transport can be done knowing stray current risks are being managed as part of the wider system safety.

We would like to extend sincere thanks to Dr. David Buxton, MICorr of Intertek CAPSIS for his valuable contribution to this article.

If you’d like to know more, please visit our Training page whereby we run our Fundamentals of Corrosion and Cathodic Protection Certification Scheme.

Ensuring Confidence in ICorr Professional Credentials

ICorr is committed to maintaining the integrity and credibility of its professional memberships and certifications. These credentials represent recognised standards of competence, professionalism, and commitment within the corrosion and asset integrity industries.

The official method to confirm the authenticity and current validity of an individual’s ICorr membership or certification is to contact ICorr Headquarters directly.

Verification requests may include, but are not limited to:

• ICorr Membership Grades, including Fellow (FICorr) and Professional Member (MICorr)
• ICorr Protective Coatings Inspector Certifications (Levels 1, 2 and 3)
• ICorr Cathodic Protection Certifications (Levels 1, 2 and 3)
• Other ICorr qualifications and professional credentials

For any questions regarding ICorr memberships, certifications, or professional qualifications, please contact admin@icorr.org.

Our team will be pleased to assist with verification enquiries and help ensure that employers, clients, contractors, and members of the public can have confidence in the credentials presented to them. By working together to verify professional credentials, we can help protect the integrity of the profession and safeguard individuals and organisations from fraudulent certification or membership claims.

ICorr recognises the importance of secure and accessible credential verification and is actively exploring future improvements to its systems that will enable online verification capabilities.

As we celebrate Volunteers’ Week, we would like to extend our sincere thanks to all our volunteers across the Institute of Corrosion.

 “ICorr’s success is built on the dedication of volunteers who generously share their knowledge, experience and time. Their contributions not only strengthen our Institute but also help develop the next generation of corrosion professionals and advance professional standards across our industry. On behalf of ICorr, I would like to thank all our volunteers for their commitment and service.” (Dr. Yunnan Gao, ICorr President)

Volunteers are at the heart of ICorr. Across our branches, committees, technical groups and professional registration activities, members generously contribute their time, expertise and enthusiasm to support both the Institute and the wider corrosion profession.

 Whether organising branch events, mentoring early-career professionals, supporting student seminar programmes, contributing to technical committees, or assisting with professional registration assessments and interviews, our volunteers play a vital role in maintaining professional standards, sharing knowledge, and helping others develop their careers.

This year, ICorr has launched the Skills for Corrosionists training series, an online initiative developed in collaboration with our Midlands Branch to address the growing need for professional and interpersonal skills development among corrosion professionals in the early stages of their careers. The programme has been made possible through the dedication and commitment of volunteer organisers and presenters who are passionate about supporting the next generation.

Another excellent example is the ICorr Regional Research Exchange, jointly organised by the North West and Yorkshire & Humber Branches in collaboration with Young ICorr, the University of Leeds and the University of Manchester. This initiative provides an important platform for students, researchers and industry professionals to share knowledge, build networks and strengthen links between academia and industry.

Behind these and many other activities are volunteers who give their time to help ICorr deliver value to its members and the wider engineering community. Their commitment ensures that the Institute continues to promote professional excellence, support career development and advance the understanding and management of corrosion.

To all our volunteers, thank you for your dedication, expertise and service. Your contribution is essential to the continued success of ICorr and the development of the corrosion profession.

If you would like to become involved and contribute to the work of the Institute, please contact admin@icorr.org with the subject line “Volunteering Opportunity”.

Join us in Dublin for the EUROCORR 2026! This year, the conference theme is “Investing in our future: corrosion challenges for green technologies”, organized by ICorr together with EFC, IoM3 and Dechema. This also incorporates the 67^th Corrosion Science Symposium as a dedicated parallel session organized by ICorr’s Corrosion Science Division (CSD).

Key accompanying events include a Careers Fair, Women in Corrosion event, Young EFC events and a summer school on green technologies

With a strong emphasis on innovation, collaboration, and early-career engagement, EUROCORR provides a prestigious platform for presenting cutting-edge research and fostering global connections within corrosion science and engineering.

As the largest international scientific conference in the corrosion field, this will be the perfect opportunity to showcase your brand to a highly targeted and engaged audience. With 1500 delegates expected to attend from both industry and leading practitioners in academia, EUROCORR 2026 is a strong platform for visibility, networking, and collaboration.

Conference Sponsorships

Find our wide range of sponsorship opportunities here or alternatively, to discuss any of our sponsorship opportunities, please email gareth.hinds@npl.co.uk