EN 50121 Railway EMC Standards

Our Expert Services department backed up by our accredited test facilities can help you understand the correct practical application of the EN 50121-X series of Railway standards.

EN 50121-X series

This series of standards is one of the main tools available for addressing the Essential Requirements of the EMC Directive (2014/30/EU). EMC Management lays down the framework for demonstrating EMC in the railway environment, and testing can be of paramount importance to close out hazards.

EN 50121-X is divided into parts

Part 1 provides a general introduction, describes the railway environment and defines the management of EMC between rolling stock and the infrastructure; it calls upon EN 50238.

Part 2 is concerned with the interface between the railway system and the outside world. It defines limits of emissions and appropriate measurement techniques.

Part 3 is sub-divided

  • 3-1 covers the train and complete vehicle, emission limits and measurement techniques are defined
  • 3-2 covers train-borne apparatus. Emission limits, immunity levels and measurement methods are specified. This standard also defines, immunity criteria, which in general are more stringent than the generic standards

Part 4 covers signalling and telecommunication apparatus. Emission limits, immunity levels and measurement methods are specified.  Part 4 is also the part that any other apparatus that does not fit into the other parts is tested to.

Part 5 covers fixed power supply apparatus and installations, for example traction sub stations.

Current version

The latest version varies dependent on the part in question, between 2015 and 2017. The 2006 version of EN 50121 is still current and is harmonised; all later versions require an update to the Official Journal before becoming harmonised.

Additional Rail Standards

In addition to the EN 50121-X series, there may be other requirements that manufacturers need to consider which may be defined in Railway Group Standards, London Underground standards/guidance, or Network Rail specific documents.

How we can help

We have an excellent understanding of the EN50121-X series of railway standards, the railway group standards and Network Rail / London Underground standards and guidance. This enables us to help you achieve both administrative and regulatory compliance

  • Our Expert Services department can help with all aspects of railway EMC compliance
  • Our test laboratories can test your product for compliance with the appropriate standards including, where applicable, on-site testing
  • To bring you up to speed with your obligations and how to best achieve them in a cost and time effective manner we offer a variety of training courses tailored to the Railway industry which can be held at your premises or Eurofins York

For more information please contact us.