Are Wi-Fi and 5G safe? What UK health advice says

UKHSA's page on policy and regulation explains how the guidelines are applied in the UK:

• UK policy follows them through a 1999 EU Council Recommendation (1999/519/EC), which refers to ICNIRP's 1998 guidelines.
• Mobile network operators have voluntarily agreed to comply with ICNIRP through codes of practice.
• Since 2021, UKHSA reports, an Ofcom spectrum licence condition has required licensees to make sure equipment above a certain power level meets ICNIRP's public guidelines, and to keep records showing how.
• Some products show compliance through product safety law: the Electrical Equipment (Safety) Regulations 2016 or the Radio Equipment Regulations 2017.

UKHSA's 5G guidance adds that current technical standards drawing on ICNIRP apply to 5G products. For masts in England, UKHSA points to the National Planning Policy Framework, which tells councils not to set health safeguards that differ from ICNIRP's, and the industry has voluntarily committed to supply a certificate of ICNIRP compliance with planning applications for base stations. Scotland, Wales and Northern Ireland have their own planning policy. How mast applications work is covered in our guide to mobile mast planning rules near your home.

Wi-Fi, mobile phones, TV and radio broadcasts and microwave ovens all use radio waves. They're non-ionising radiation, which UKHSA defines as the part of the electromagnetic spectrum that doesn't carry enough energy to cause ionisation in living matter.

UKHSA and WHO both say the main biological effect of radio waves is heating, and WHO says everyday exposure levels are very much lower than those needed for significant heating, causing a negligible rise in temperature. ICNIRP's limits are built around that:

• ICNIRP concluded that exposure below the heating threshold is unlikely to be linked to adverse health effects.
• For the public it applies a reduction factor of 50, giving a whole-body limit of 0.08 watts per kilogram averaged over 30 minutes. That's measured as the specific absorption rate (SAR), the rate at which the body absorbs radio energy. Public limits are stricter than those for workers.
• ICNIRP says its method is conservative and there's no evidence that extra precautionary measures would benefit population health.

At higher frequencies, UKHSA says, radio waves penetrate the body less and any heating is more confined to the surface. Distance matters too: the highest public exposure comes from a mobile phone held close to the body, such as against your head, for a voice call. A router on a shelf is a different situation, which is why UKHSA's advice treats the two differently.

Home Wi-Fi works in radio bands near 2.4, 5 and 6 gigahertz (GHz), and if you're using it or near a Wi-Fi device your body absorbs some of the energy sent out. UKHSA's guidance then makes three points:

• The signals are very low power: typically 0.1 watt (100 milliwatts), in both the router and the device connecting to it.
• The frequencies aren't unusual: UKHSA says they're broadly the same as those of other radio uses such as FM radio and mobile phones.
• Measured exposure is small. UKHSA's predecessor, the Health Protection Agency, measured Wi-Fi in schools. Exposures were small compared with the ICNIRP guidelines, Wi-Fi devices' time-averaged output was generally lower than mobile phones', and exposure was likely lower than from a phone call because the antennas tend to be further from the body.

Those results fed into the 2012 review by the Advisory Group on Non-ionising Radiation (AGNIR), an independent expert group. UKHSA's conclusion is that there's no reason to stop using Wi-Fi.

UKHSA's 5G guidance starts with context: over the decades, networks have moved towards more, smaller transmitters with lower radiated powers, and measurements continue to show public exposure well within the ICNIRP guideline levels used in the UK.

As 5G rolled out, UKHSA measured exposure around 5G macro base stations (the larger masts), published in the peer-reviewed journal Bioelectromagnetics. It found 5G exposure well below the guidelines and generally lower than or similar to 4G, and its advice stayed the same. UKHSA says adding 5G may slightly increase overall exposure, but it should remain low relative to the guidelines, with no consequences for public health.

• The limits already include children. ICNIRP writes its public limits for people of all ages and health states, including more vulnerable groups, which is why they're stricter than worker limits. Its 2020 review included evidence on health in children.
• The UK review found nothing convincing. AGNIR's 2012 review, cited by UKHSA, found no convincing evidence that exposures below guideline levels cause health effects in adults or children.
• UKHSA sees no reason to stop using Wi-Fi in schools. Its Wi-Fi research looked specifically at schools, and it sees no reason why Wi-Fi shouldn't continue to be used, including in education.

The one piece of child-specific advice is about mobile phones, not Wi-Fi. The Independent Expert Group on Mobile Phones advised, and the government accepted, that excessive mobile phone use by children should be discouraged. So if you want to act on anything, it's long calls with a phone held to the head, not the router. UKHSA says moving the phone away from the body, as when texting, gives very much lower exposure.

The guidance on pregnancy is reassuring, and it comes from more than one source:

• ICNIRP's guidelines protect pregnancy. The 2020 guidelines treat a fetus as a member of the general public in every exposure situation, and a pregnant woman as a member of the general public for its basic restrictions (the core limits). So the stricter public limits apply.
• No substantiated effects. ICNIRP found that no adverse effects of radio wave exposure on fertility, reproduction or development relevant to human health have been substantiated. It also found no substantiated evidence that a mother's mobile phone use affects her child's development.
• WHO's view. WHO's questions and answers on electromagnetic fields (2016) say the overall weight of evidence shows that exposure at typical environmental levels does not increase the risk of adverse pregnancy outcomes such as miscarriage, malformations or low birth weight.

None of the UKHSA, ICNIRP or WHO guidance we read advises pregnant women to avoid Wi-Fi, 5G or living near a mast. If you have concerns about your pregnancy, your midwife or GP is the right person to ask.

In May 2011 the International Agency for Research on Cancer (IARC) classed radio waves as Group 2B, "possibly carcinogenic to humans". UKHSA explains that this was largely based on mobile phone use: IARC found limited evidence for two types of tumour (glioma and acoustic neuroma) among wireless phone users. For environmental exposures, including wireless telecommunications such as networks and masts, it found the evidence inadequate to draw conclusions either way.

Research has continued. WHO's statement, which UKHSA still quotes, is that no adverse health effect has been causally linked with wireless technologies. SCHEER (the Scientific Committee on Health, Environmental and Emerging Risks) published its latest opinion in April 2023, which UKHSA describes as broadly in line with UKHSA, ICNIRP and WHO. The UK government supports ongoing studies at Imperial College London, including COSMOS and SCAMP.

Some people report symptoms such as headaches or tiredness that they link to Wi-Fi, phones or masts, sometimes called electromagnetic hypersensitivity (EHS).

UKHSA says reviews by WHO, SCHEER and AGNIR suggest the symptoms people report are not directly related to electromagnetic fields. It adds that this doesn't undermine the symptoms, and other causes should be considered. WHO says scientific evidence doesn't support a link between these symptoms and exposure, and that treatment should focus on the symptoms rather than on reducing fields at home or work. ICNIRP found no substantiated reports of effects on symptoms and wellbeing apart from pain caused by raised temperature at high exposure levels.

In practice, if you feel unwell, see your GP and describe your symptoms fully, so that other causes can be looked into.

UKHSA says people may wish to reduce their exposure, and it's specific about where that's worthwhile:

For phones, UKHSA lists these measures:

1. Text, or use the phone held away from your body, which gives very much lower exposure than holding it to your head.
2. Use a hands-free kit.
3. Keep calls short.
4. Make calls where the signal is strong.
5. Choose a phone with a low SAR value, as quoted by the manufacturer.

UK health advice doesn't give a reason to pick one type of broadband over another. Full fibre, cable and part-fibre broadband come into the home through a wire, but inside the home they're usually shared over Wi-Fi, which UKHSA's Wi-Fi advice covers. 4G and 5G home broadband use the mobile network, which its 5G and base station advice covers. The same ICNIRP guidelines sit behind both.

What should decide it is what's available at your address, the speed you need, the contract length and the price. You can compare broadband deals at your postcode through our partner's comparison, which shows live deals from a range of providers, or browse every provider we cover. If full fibre has reached you, fibre broadband deals are a good place to start. We don't switch you ourselves; you order from the provider you choose.