What is SAGE?

SAGE stands for Stakeholder Advisory Group on Extremely Low Frequency Electric and Magnetic Fields (EMFs). It is a UK group set up in 2004 to consider possible precautionary measures in relation to EMFs.


First Interim Assessment
   Response - Health Protection Agency
   Response - Department of Health
Second Interim Assessment

Electric and magnetic fields are produced wherever electricity is distributed or used, so the entire population is exposed to them to varying degrees. It is known that they can have health effects at higher levels than those to which people are normally exposed, but there is also concern that they may have health impacts at lower levels - including those to which people are exposed. Fields (a least at low levels) due to internal wiring circuits can be found in virtually all homes, but in some (and particularly those near to external power lines) the fields may be higher. The combination of scientific uncertainty, the health issues involved and the numbers of people potentially affected has resulted in this being a highly controversial and emotive topic.

In 2004, the then National Radiological Protection Board (NRPB) recommended new guidelines which set magnetic field levels above which members of the public should not usually be exposed and the UK Government accepted these. However, this left open the question of what effects (if any) fields below these levels have on people and what precautionary measures (if any) should be taken. SAGE was formalised in November 2004 to involve all key stakeholders in addressing these issues.

The aim of the SAGE process, as agreed by stakeholders in November 2004, was: to bring together the range of stakeholders to identify and explore the implications for a precautionary approach to ELF EMF (electric and magnetic fields) and make practical recommendations for precautionary measures. The remit of SAGE is to provide advice to Government. It is then for Government to take decisions on policy.

SAGE Phase 1

SAGE published its First Interim Assessment in April 2007 in which it recommended a series of measures which government might take to mitigate the effects of exposure to extremely low frequency electric and magnetic fields. The response from the three government departments involved - Departments of Health, Energy and Climate Change and Communities and Local Government - which was finally made in October 2009, prompted very different reactions among SAGE members.

The recommendation to optimally phase high voltage overhead powerlines was accepted, although it was noted that the majority of overhead lines are already optimally phased. The option of implementing "no build corridors" was not adopted, with the government stating that it was a disproportionate measure in the light of the existing evidence for childhood leukaemia alone. Outside of the SAGE proposals, the government also chose to use the response to make an explicit statement that ICNIRP is the reference level for unacceptable exposure in planning guidance documents for new build. The recommendation for manufacturers to investigate low field appliances was neither adopted nor rejected, with the government considering it a matter for industry only. A recommendation on providing more information to the public was accepted.

There were six house wiring recommendations, of which three were rejected: radial final circuits instead of ring final mains power circuits was rejected on the basis of the opinion of the IET wiring regulations committee, as was the recommendation to keep 'go-and-return' circuits together. The other rejected recommendation was to make routine EMF measurements available as an option in house surveys, which the government considered impractical as there were no international standards in place against which to evaluate measurements. However, the possibility of this being available to some customers was not explicitly rejected. Two of the remaining wiring recommendations were accepted (protect whole installations with a residual current device (RCD), and replacing rotating-disk meters with electronic meters), with the government stating that no extra action was required on either, as existing practice ensured that these recommendations would happen anyway. The final recommendation, that consumer units were placed away from high occupancy areas, was neither adopted nor rejected.

The response produced mixed reactions from the SAGE membership for a number of reasons: some members felt that all of the recommendations produced by the group had been put forward after a large investment of time and expertise, and as such had been considered in enough detail that all should have been adopted. Some felt that the decision of government explicitly to use ICNIRP guidance levels in planning documents was inappropriate when SAGE had been set up to address the potential health effects of considerably lower magnetic fields. Others felt that the rejecting of house wiring recommendations was an unfortunate outcome caused largely by the IET wiring committee not having had input from SAGE members, and therefore not being completely aware of all the considerations that led to the recommendations being put forward - the addition of which may have helped the recommendations to have been adopted. Still others felt that the government statement brought clarity as to the EMF policies in place in the UK, that the decisions made were all based to some extent on the evidence, and at least some appropriate precautionary policies had been introduced, all of which means the process should be regarded as largely successful.

It was recognised that the government only adopted recommendations where the investment of time or money required to implement them was very low or no-cost (either the recommendation was handled by existing practice or was a low cost measure in its own right), and this guided the recommendations that were produced from SAGE Phase 2.

Despite these differences, the SAGE process continued into its second phase during which it examined the science behind the EMF issue and matters related to the distribution of electricity from sub-stations to the home. SAGE's second interim assessment was published in June 2010 and the SAGE funding organisations and process group members are currently preparing a draft programme of work for SAGE's third phase to put to its full membership for comment and approval which, it is hoped, will begin work in the winter of 2010-2011, budgetary constraints notwithstanding.

SAGE Phase 2

After 2007 there was a lull in SAGE activity but it then restarted, looking principally at precautionary measures for EMFs from distribution systems. The Second Interim Assessment was published in June 2010. It makes many recommendations relating to distribution networks, many endorsing existing best practice. It also reports a Science Forum within SAGE. The document can be downloaded from here.


The dialogue is funded jointly and equally by the Department of Health, CHILDREN with LEUKAEMIA and the National Grid. This balanced arrangement helps to ensure that no single funding body can exert inappropriate influence over the process.

Process Management

SAGE does not have a conventional chairman and instead employs a professional, independent facilitator who works on behalf of all the stakeholders involved. The process is intended to be more inclusive and transparent than traditional approaches and there is an emphasis on exploring and understanding rather than just defending existing positions. The process currently includes "Main Group" meetings for all stakeholders (effectively the governing body for SAGE), smaller and more frequent working group meetings on particular issues, an on-going Science Forum, and occasional technical seminars.

The convening, facilitation and project management services for SAGE Phase 2 are provided by Golder Associates, in partnership with Nigel Westaway as lead facilitator and process designer.

Access to SAGE Documents

Documents generated in Phase 1 include a mixture of unrestricted and confidential material. The confidential material is only accessible to ongoing SAGE members (ie those who were members of Phase 1 and have continued into Phase 2). In Phase 2, there is a presumption that all documents will be unrestricted unless there is a clear reason to treat them as confidential. Most of the Phase 2 documents on this website are therefore accessible to anyone. Any confidential material will accessible only to SAGE Phase 2 members.