Exposure limits

Various bodies have set limits or published guidelines on exposure to EMFs.  Most have set the limits to prevent established effects at high fields - principally induced currents - but have not regarded the evidence for effects at lower fields such as cancer as strong enough to justify setting exposure limits.  But there is a debate as to what might be appropriate precautionary measures at these lower fields.


Legal position in various countries

We set out the position in various countries:

Exposure limits from specific organisations

Here we give the details of specific exposure limits with the actual numbers: old NRPB limits from 1993 and the newer NRPB limits from 2004, the ICNIRP guidelines from 1998, the European 1999 Recommendation on public exposure and the 2004 Directive on occupational exposure, and the ICES standard from 2002.

Recent developments

In 2010, ICNIRP issued new exposure guidelines for the range of frequencies that includes power-line EMFs.  This followed a consultation on draft guidelines during 2009.

Indirect effects

Indirect effects are effects caused by objects which are charged up by the electric field - "microshocks" and surface charge effects.  We detail how these indirect effects are treated in the various exposure limits here.

Limits at different frequencies

The information on this site is for the frequency of mains electricity in the UK, 50 Hz.  Some limits are the same at 60 Hz (as used in America) and some are different - see a list here.  MCL have a useful calculator to tell you the limits at other frequencies.

We also provide a short summary of limits for static fields.

Exposure limits quick links

Compilation of limits in different countries

The international ICNIRP limits, the basis of the limits in many countries

The legal position in the UK and the EU

Key UK Documents

UK policy on exposure limits for the public is set out in three key documents:

Written Ministerial Statement
sets the policy

National Policy Statement EN-5
applies it to power lines

Codes of Practice
give the practical details