General EMF queries

Published: 6 March 2024

This page answers some questions you may have about Ofcom's role in relation to electromagnetic fields (EMF).

Ofcom authorises and manages the use of radio spectrum in the UK through the issue of licences and/or by setting conditions for spectrum use on a licence-exempt basis.

We also measure radiofrequency electromagnetic fields (EMF) levels and can take action against licensees in the event of a breach of the internationally agreed levels on EMF exposure. We have a wide range of enforcement powers available to us in the event of non-compliance, including the power to impose fines, instigate criminal proceedings and revoke spectrum licences, if considered appropriate.

We are not a public health body. The UK Health Security Agency (UKHSA) are responsible for public health matters associated with EMF and we take into account their advice when carrying out our spectrum management functions. UKHSA’s main advice is that EMF levels should comply with the internationally agreed levels in the ICNIRP Guidelines. Any questions on the potential impact on health of devices emitting electromagnetic radiation should therefore be directed to UKHSA. Further information on the remit of Ofcom and UKHSA is available in our statement on EMF compliance (PDF, 1.1 MB) (see Section 3) and our update on EMF compliance (see Section 3).

We also have no involvement in the planning process for physical structures such as masts, buildings etc that may host radio equipment, which is a matter for local planning authorities. Further information is available on our masts and planning webpage and in our statement on EMF compliance (PDF, 1.1 MB) (see paragraphs 4.37 – 4.43).

The Department for Environment, Food & Rural Affairs is the UK government department responsible for safeguarding our natural environment.

5G is regulated in a number of ways. Ofcom’s role is to work with the Government and industry to help the UK become a world leader in 5G.

We provide further information on Ofcom’s role in relation to 5G on our ‘What is 5G?’ webpage and our discussion document, Enabling 5G in the UK.

Our annual plans of work includes the work we plan to do in relation to 5G.

As the communications regulator we collect information, which includes information supplied by UK mobile network operators about their mobile phone sites, for example, to assist with our Connected Nations and infrastructure reports.

However, HM Government has raised significant concerns with Ofcom about the release of information about the location of mobile phone masts on national security grounds and has advised that disclosure of this information would adversely affect national security.

Taking into account Government’s advice, our current view is that the reasons in favour of withholding information on the location of mobile phone masts outweighs the public interest in disclosing it.

Further information on the relevant statutory framework and recent public interest assessments we have carried out are available on our website.

Ofcom does not hold information about where and when telecoms masts or 5G will be rolled out in the future.

Mobile network operators (MNOs) have licences issued by Ofcom which authorise the use of blocks of spectrum on a national basis on the basis of technology and service neutrality.  MNOs self-plan their rollout of mobile sites and technology across the UK and can decide what technology to use or service to provide in a particular frequency band as long as it complies with the technical conditions we have set.

Copies of MNOs’ licences are published on our website at mobile and wireless broadband below 5 GHz and mobile and wireless broadband above 5 GHz. Other technical information relating to MNOs’ licences is published under ‘Frequency and technical information’ on our mobile and wireless broadband page.

MNOs’ websites may however contain information relating to their future plans for 5G deployment and all four MNOs (Vodafone, O2, EE and Three) have coverage prediction maps on their websites, available to the public, which can be searched to see whether an area has 5G coverage.

Ofcom carries out measurements of EMF exposure levels near mobile phone masts. Our website provides information on recent testing and measurements of EMF levels that we have taken near mobile phone masts. Our published measurements have consistently shown that EMF exposure levels are well within the internationally agreed levels published in the ICNIRP Guidelines.

We only hold information on EMF exposure levels in the locations identified in the reports on our website.  We will however continue to undertake EMF measurements and publish the results on its website.

If you want information on EMF exposure from a mast in your area that is not identified in our website, you can request Ofcom to undertake measurements. Further information on this service is available on our website.

Mobile network operators (MNOs) have licences issued by Ofcom which authorise the use of blocks of spectrum on a national basis. MNOs self-plan their rollout of mobile sites and technology across the UK although may require planning permission, for example, if building a new mast or for some upgrades to existing masts.

Ofcom has no involvement in the planning process for physical structures that may host radio equipment (such as masts, buildings, lampposts or other street furniture), or in the enforcement of planning law. This is a matter for local planning authorities. The responsibility for planning policy falls to the DLUHC - Department for Levelling Up, Housing and Communities. In particular, Section 10 (Communications) of the National Planning Policy Framework (2021) outlines the planning criteria for communications infrastructure for England.

There are also codes of practice in England and Wales which explain that MNOs are committed to compliance with internationally agreed levels of exposure to electromagnetic fields and requires MNOs to sign a declaration confirming that they have complied with these levels when applying for planning permission for a new site or a change to an existing site.

Individual planning authorities administer the planning laws locally and issue permission to build through the normal planning process. If you have any views or questions about planning applications for any specific site, you can address those to the relevant local planning authority.

Further information is available on our Masts and planning page and in our statement on EMF compliance (PDF, 1.1 MB) (see paragraphs 4.37 – 4.43).

In the UK, The UK Health Security Agency (UKHSA) takes the lead on public health matters associated with radiofrequency electromagnetic fields (EMF), and has a statutory duty to provide advice to Government on any health effects that may be caused by exposure to EMF. UKHSA publishes information on the possible health effects of EMF exposure on its website.

UKHSA’s main advice is that EMF levels should comply with the internationally agreed levels in the ICNIRP Guidelines. These Guidelines cover frequencies between 100 kHz and 300 GHz and therefore cover all current and planned future use for mobile telecommunications in the UK (including new 5G services).

Published advice from UKHSA and other internationally recognised health bodies including the World Health Organisation (WHO) and the International Commission for Non-Ionizing Radiation Protection (ICNIRP) support the view that EMF exposure below the limits recommended in the ICNIRP Guidelines do not appear to have any known consequence on health.

Ofcom is not a public health body and does not have medical or health expertise. We do not hold any studies relating to potential health risks of EMF exposure. Further information on the remit of Ofcom and UKHSA is available in our statement on EMF Compliance (PDF, 1.1 MB) (see Section 3) and our update on EMF Compliance (PDF, 865.1 KB) (see Section 3).

In the short term, 5G is being deployed on existing mobile masts, but over time, may make more use of ‘small cells’ (smaller transmitters covering a smaller area), and this may include deployments on street furniture, lampposts etc.

Small cells (including any installed on street furniture) could be useful to provide capacity in specific locations with concentrated high demand for wireless broadband. While more ‘small cells’ may be needed, they will operate at lower power than existing ‘macro sites’ (i.e. existing mobile masts).

We are not aware of any evidence to suggest that the aggregate exposure to EMF from multiple small cells will be significantly different to that from macro sites. In any event, mobile operators will be required to ensure all their sites, both individually and in aggregate, do not exceed the general public EMF limits in the ICNIRP Guidelines.

We also note that some buildings, structures, lampposts and other street furniture have been used to mount radio equipment for many decades, delivering a range of services (such as public Wi-Fi and the control/monitoring of CCTV) using various technologies. Whilst some street furniture may today, and in the future, carry 5G, this is not a new concept.

Further information on 5G is available in our guide to 5G technology (PDF, 604.2 KB) and our ‘What is 5G?’ page.

Ofcom carries out measurements of EMF exposure levels near 5G enabled mobile phone masts. We have particularly focused on busy areas where we could expect to see the highest levels of mobile phone use. We have also sought to take measurements at publicly accessible locations with the highest signal strength near the mobile site (see page 12 of our EMF test summary report (PDF, 973.8 KB) for more information).

All of the measurements we have taken in this programme to date have been well within the internationally agreed limits on EMF exposure in the ICNIRP Guidelines.

We will continue to undertake EMF measurements and publish the results on our website.

Current 5G deployments are re-using frequencies that have been in use for many years. Whilst 5G will, in the future, start to use higher frequencies than those currently used by wireless networks (e.g. mmWave frequencies), the use of these frequencies is also not new. 5G is re-using spectrum that has previously been used to deliver services such as TV broadcasting, wireless broadband and satellite connections as well as for point-to-point microwave links and other types of transmitters that have been present in the environment for many years.

The internationally agreed limits in the ICNIRP Guidelines also apply to frequencies used for 5G services in the same way as they apply to frequencies used for other services.

In relation to 5G, UKHSA have said that “the overall exposure is expected to remain low relative to guidelines and, as such, there should be no consequences for public health”.

We provide further information on this question in our guide to 5G technology (PDF, 604.2 KB).

The Department for Environment, Food & Rural Affairs is the UK government department responsible for safeguarding our natural environment.

We note that none of the environmental reports or assessments referenced in the answers to questions on this topic provided by Members of Parliament have identified EMF exposure as a significant threat to the environment. Instead they highlighted key threats such as habitat loss, inappropriate pesticide use and invasive species. See, for example, where it is noted that in 2018, an EU-funded ‘EKLIPSE’ study concluded that “few ecological studies exist, but when they do, the reported [EMF] effects are negligible, contrasting, or cannot be separated from other environmental factors”.

We also note that mobile network operators and local councils are required to take into account environmental considerations when submitting/assessing planning applications for new masts. See, for example, the codes of practice in England and Wales

There is no single safe distance from a mobile phone mast. As noted by ICNIRP (the International Commission for Non-Ionizing Radiation Protection) on its website, many factors can “influence the actual exposure such as the height, tilt and direction of antenna, absorption from trees and plants or reflections from buildings, as well as distance. Distance alone is not a reliable proxy for exposure from a base station.”

The main advice from The UK Health Security Agency (UKHSA) is that the ICNIRP Guidelines should be adopted for limiting EMF exposure. Published advice from UKHSA and other internationally recognised health bodies including ICNIRP and the World Health Organisation (WHO) support the view that EMF exposure below the limits recommended in the ICNIRP Guidelines do not appear to have any known consequence on health.

We have carried out EMF measurements near mobile phone masts for many years. All of these measurements have shown levels of EMF exposure which are well within the ICNIRP Guidelines for general public exposure.

The UK Health Security Agency (UKHSA) have published information on their website regarding Wi-Fi radio waves and health. Any questions on the potential impact on health of devices emitting electromagnetic radiation should therefore be directed to UKHSA.

We also note that Wi-Fi equipment is covered by product safety legislation which sets out requirements for health and safety. Further information is available in our statement on EMF compliance (PDF, 1.1 MB) (see paragraphs 4.32 - 4.36) and on our website.

As the communications regulator we collect information, which includes information supplied by UK mobile network operators about their mobile phone sites, for example, to assist with our Connected Nations and infrastructure reports.

However, HM Government has raised significant concerns with Ofcom relating to the release of information about the location of mobile phone masts on national security grounds and has advised that disclosure of this information would adversely affect national security.

Requests for information about the location of mobile phone masts are considered under The Environmental Information Regulations 2004 (‘EIR’) rather than the Freedom of Information Act 2000. The EIR provides that we may refuse to disclose information if it would adversely affect national security and in all the circumstances of the case, the public interest in maintaining the exception outweighs the public interest in disclosing the information (regulation 12(1) and (5)(a) of the EIR).

Taking into account the Government’s advice, our current view is that the reasons in favour of withholding information on the location of mobile phone masts outweighs the public interest in disclosing it.

More information on the relevant statutory framework and recent public interest assessments we have carried out are available on our website. See:

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