UK policy

Policy on EMFs in the UK, set by Government, is made up of exposure limits plus certain precautionary measures.  Several inputs went in to forming the policy, including scientific advice from the Health Protection Agency and the stakeholder process SAGE.  You can read the details of all those by following the links.  Here, we set out the policy as it stands now, with particular reference to power lines.

See the box on the right for other places where the UK Government expresses policy on EMFs.

The policy in summary

Exposure limits

Exposures to the general public in the UK should comply with the ICNIRP 1998 exposure limits in the terms of the 1999 EU Recommendation.

In practical application this means:

  • an electric field of 9 kV/m
  • a magnetic field of 360 µT
  • both applying where the time of exposure is significant, essentially homes, other places where people might stay overnight, and schools

Precautionary measures

The UK has embraced the concept of precautionary measures, but has specified which precautionary measures will be applied to different type of equipment. In summary, the measures which apply are:

  • high-voltage overhead power lines: optimum phasing
  • low-voltage distribution: a whole series of engineering measures, mainly existing best practice, designed to reduce net currents
  • house wiring: no specific measures, recognising that existing trends should reduce fields anyway
  • substations: encouragement to site them away from homes, but no specific requirements

Application to power lines

It is up to the electricity companies to design their power lines such that they comply with the relevant limits, even directly underneath the line where the fields are highest.  There is no need for any restrictions on how close you can get to a power line in order to comply with the limits.

There are no restrictions on how close a home can be to a power line or vice versa.

Where the policy is set out

thumbnail of cover of written ministerial statementThe policy is set out in the Written Ministerial Statement of 2009 (formally, this was the Government's response to SAGE's First Interim Assessment).  The policy for power lines has two key planks: compliance with the 1998 ICNIRP exposure guidelines in the terms of the 1999 EU Recommendation, and a precautionary policy called "optimal phasing". 

thumbnail of cover of EN5The policy is then formally applied to power lines by National Policy Statement EN-5.  In terms of legislation, this applies only in England and Wales, but it sets the principles for the whole of the UK - see more on which bits of policy apply in which bits of the UK

 

 

 

thumbnail of cover of code of practiceAll the practical details needed to apply the policy of compliance with exposure limits is contained in a Code of Practice.  This says what land uses the limits apply to, what conditions compliance is assessed for, how accurate the calculations need to be, and so forth.

Download the Code of Practice

Part of the system for establishing compliance that the Code of Practice establishes is a list of equipment that inherently complies with the exposure guidelines, and that can be found in this section of this website.

thumbnail of cover of phasing copAnd the practical details of the precautionary policy of optimal phasing are contained in a second Code of Practice.

Download the Code of Practice


 

thumbnail of cover of G92

For low-voltage distribution networks, the agreed precautionary measures are set out in Engineering Recommendation G92 published by the Energy Networks Association.  This implements the outcome of SAGE's Second Interim Assessment.