Railway EMC Standards

Electromagnetic compatibility in railways is a very broad and complex issue.  The locomotives, railcars, carriages and wagons are all sources of electromagnetic emissions and are all vulnerable to electromagnetic interference.  Railway stations have the added complication of hundreds and in peak periods of thousands of electronic devices being used by passengers in a small area.  We can be sure that these devices will be used most actively when there is some disruption or unusual situation in the railway.

A few of the relevant standards are discussed in this section.  The discussion is certainly not complete and may not be relevant to your situation but is offered to provide some background information.  Each country has its own legislation that may be much more stringent than the standards listed here and within Europe there is additional European legislation in the form of EMC Directives.

Whole Railway

Achieving electromagnetic compatibility (EMC) in this situation is not a simple process.  There is no single standard and no guarantee that applying any or all available standards will avoid problems.  In fact, while we can be confident that applying standards will reduce the risk of problems, the standards themselves emphasise that problems can remain.

The most broadly applied railway EMC standard (outside the USA) is the European Standard EN 50121.  This standard is also available as an International Standard (IEC 62236) but the EN document is more commonly cited.

Signalling Systems

Railway signalling systems are used to manage the separation between trains and to optimise train movements.  EMC aspects of the traditional train detection systems are covered by EN 50238, including axle counters.  There are extensive provisions for electromagnetic compatibility in the EMC sections of the ERTMS standards and documentation.  Many metro systems and some locomotive and railcar manufacturers use the USA based UMTA standards.  Most railways have their own standards in addition, dealing with specific applications and conditions.

Rolling Stock

Rolling stock or rollingstock (which includes locomotives, passenger cars, EMU, DMU, track machines and freight wagons) are covered by the EN 50121 series of standards, with particular requirements for the components of the rolling stock and for the complete vehicle.  In addition, standards such as EN 50343 deal with EMC considerations for cables on rolling stock.  EN 50500 prescribes procedures for measuring human exposure to magnetic fields in the railway environment.

Outline of Selected Standards

"The enemy of safety is complexity."

 Behind Human Error, Woods et al, Ashgate 2010 p 23

"Knowledge and error flow from the same mental sources, only success can tell one from another."


Ernst Mach, 1905