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EMF deadline looms

Connect, no. 144, September - October 2006, p.2

EMF survey on the shop floor
EMF survey on the shop floor

With only 18 months to go before the Physical Agents Directive, limiting workers' exposure to electromagnetic fields (EMFs), becomes law, companies should act now to ensure that they have systems in place to ensure compliance with the Directive and, in the UK, the implementing regulations. These regulations will have a major impact on manufacturers, operators and users of welding and nondestructive testing equipment and installations where exposure to electromagnetic radiation needs to be considered.

The main processes believed to produce significant EMFs are:

  • Resistance welding
  • Some arc welding processes eg pulsed MIG and TIG
  • High frequency welding processes as used in plastics
  • Magnetic particle inspection
  • Induction heating

The Directive, which comes into force in April 2008, places a range of duties on employers, the most significant of which are:

  • To assess and measure levels of electromagnetic fields (EMFs) to which workers are exposed
  • Where these levels exceed 'action values', to assess whether exposure limits are overstepped
  • To ensure that exposure limits are not exceeded
  • To erect warning signs where EMF levels may cause exposure limit values to be exceeded
  • To provide appropriate information and training

Companies using any of the above processes are advised to act now and make an assessment of the EMF levels on the shop floor and to put into place a plan to be ready for 2008.

TWI has experience of measuring and interpreting the results of EMF surveys and has now purchased a Narda ELT-400 exposure level tester. This test instrument displays the field as a percentage of the 'action values'.

An EMF project was recently carried out by TWI for the HSE and the report is available on their website, see

TWI can assist companies with meeting the Directive. We can advise on the risks from welding processes, provide workplace assessments and guidance on minimising EMF exposure.

If you need help in meeting the Directive, are interested in TWI carrying out a site survey or require further information, please contact Geoff Melton. E-mail:

For more information please email: