EMF Safety

Working with Magnetic Fields In NDT

What is new?

As of the 1st July 2016 the European Directive 2013/35/EU came into effect which outlines the minimum health and safety requirements regarding the exposure of workers to the risks arising from electromagnetic fields (EMF) and is legally enforceable within all member states.

Presently there is no reason to believe that the UK’s decision to leave the EU will invalidate this directive. All existing EU regulation is expected to be written into UK law under the proposed 'Great Repel Bill'.

Where can I read the EMF directive?

Download EMF Directive

EMF Demagnetiser

What does this mean practically?

Equipment generating electromagnetic fields should be risk assessed and employers must take necessary actions to ensure the risks arising from EMF at the workplace are eliminated or reduced to a minimum.

EMF Hazard Symbols

What are the risks?

While there is presently no conclusive evidence supporting any long term health impacts from low frequency EMF exposure, the directive lists a number of short term health and safety concerns.

These include:

  • Localised tissue heating
  • Muscle stimulation
  • Vertigo
  • Phosphenes 
  • Interference with medical equipment
  • Projectile risk
  • Fire and explosive risk

Magnetic Field Survey Service

Johnson & Allen make risk assessment easy - We now offer an in-house magnetic field survey service for any location in the UK.

Our professional engineers perform a full risk assessment for equipment (or premises) by taking a number of field measurements using equipment specially designed for determining compliance with the EU directive. Johnson & Allen will then produce a full report including the results, a conclusion and list a number of recommendations to pragmatically reduce EMF exposure and give employers and operators peace of mind.

EMF MPI Bench Unit


EMF Action Level Chart

What equipment produces EMF?

In theory any piece of electrical equipment or magnet.

Of course in reality most general electrical products do not produce EMF emissions any where near the action levels listed in the directive. However MPI necessitates the use of strong magnetic fields to find defects.

Thus attention should be given to equipment such as:

  • MPI Bench Units
  • Power Packs
  • Demagnetisers
  • Yokes
  • Permanent Magnets
  • Bespoke Units

What else is Johnson & Allen doing?

While Johnson & Allen makes every effort to provide accurate information for our standard products the nature of MPI and engineering in general creates the need to risk assess in-situ.

Employers should consider:

  • How MPI equipment is used
  • Exposure time to EMF and shift patterns
  • Two or more pieces of equipment in proximity may behave differently
  • Through-traffic near to inspection areas
  • The impact of EMF on the other side of walls or partitions
  • Equipment performance may change over time

Johnson & Allen will continue to update their product literature but we suggest customers with concerns or unanswered questions email our Sheffield head office at: