A Beginner's Guide to EMF and Anti-Radiation
EMF stands for electromagnetic field. It's the energy produced by anything that uses or transmits electricity, from house wiring and appliances to Wi-Fi routers and mobile phones. This beginner's guide explains the different types, where they come from in an ordinary home, how they're measured, and what your practical options are if you decide you'd like to reduce them.
What is EMF, in plain terms?
Wherever electricity flows, it creates fields around it. Some of these stay close to the source and fade quickly, like the field around a mains cable. Others are deliberately sent out as radio waves to carry information, like Wi-Fi and mobile signals.
"EMF" is used as a catch-all for all of these, which causes a lot of confusion, because the different types behave differently and need different instruments to measure.
What are the main types of EMF?
| Type | Common sources at home | Measured in |
|---|---|---|
| Radiofrequency (RF) | Wi-Fi, mobile phones, masts, smart meters, cordless phones, Bluetooth | V/m or µW/m² |
| Low-frequency magnetic fields | Wiring, consumer units, appliances, transformers | milligauss (mG) or microtesla (µT) |
| Low-frequency electric fields | Cables, lamps, extension leads | V/m |
One more distinction matters: all of these are non-ionising. That's different from ionising radiation such as X-rays and radioactive sources, which carry enough energy to damage DNA directly. The word "radiation" gets used for both, which is where a lot of alarm comes from.
Where does EMF come from in a typical home?
- Your router — usually the most constant radiofrequency source in the house
- Mobile phones — transmit in bursts, harder when signal is weak
- Outside sources — masts, neighbours' Wi-Fi, street equipment
- Smart meters — transmit briefly and periodically
- The consumer unit and wiring — low-frequency magnetic fields, strongest close up
- Plug-in items near beds and desks — low-frequency electric fields
Most of these fall away quickly with distance. That single fact is the basis for most practical steps.
What do UK regulators say?
UK policy is based on guidelines from ICNIRP, the International Commission on Non-Ionizing Radiation Protection. These set reference levels for exposure, and typical domestic exposures sit well below them. UK and international health bodies do not consider harm to be established at exposures below these guidelines.
Some people choose to reduce their exposure further anyway, as a precaution. That's a personal decision. Our approach is to give you the tools to measure what's actually there and make that decision on evidence, rather than to tell you what to worry about.
How do you measure EMF?
With a meter, and the right type of meter for the type of field.
- An RF meter measures wireless sources: Wi-Fi, phones, masts
- A low-frequency meter measures wiring and appliances
An RF meter reads close to zero beside your consumer unit, and a low-frequency meter reads close to zero beside your router. Neither is wrong; they measure different things. Phone apps can't measure radiofrequency at all.
Our EMF detectors, including the Safe and Sound Pro II, come with calibration certificates. For how to use one, see our step-by-step guide to finding EMF hotspots in your home.
What can you do to reduce EMF?
In order of cost, cheapest first:
- Increase distance. Move routers away from where you sit and sleep; keep the phone off your body.
- Switch off. Router timer overnight, phone in airplane mode.
- Go wired. Ethernet for desks, wired or air tube headsets for calls.
- Shield specific spots. A bed canopy, wall treatments, a laptop shield, or a phone case.
For a room-by-room walkthrough, our bedroom EMF checklist is the place to start.
How do you tell a real product from a gimmick?
Ask for a number. A genuine shielding product states its attenuation in decibels at a stated frequency, and you can check it with a meter.
Be sceptical of stickers, chips, pendants and anything else sold without a tested figure. They don't produce a difference a meter can detect. We cover this in more detail in household items that reduce EMF.
Where to go next
- How to find EMF hotspots in your home
- Reducing EMF in your bedroom: a checklist
- Do EMF phone cases work?
- 5G protection explained
- Why do Faraday bags stop working?
Frequently asked questions
What does EMF stand for?
Electromagnetic field. It's the energy produced by anything that uses or transmits electricity, including wiring, appliances, Wi-Fi and mobile phones.
Is EMF the same as radiation?
EMF from household electricity and wireless devices is non-ionising radiation. It's physically different from ionising radiation such as X-rays, which carries enough energy to damage DNA directly. The shared word causes a lot of confusion.
What is an EMF reader?
A meter that measures electromagnetic fields. RF meters measure wireless sources; low-frequency meters measure wiring and appliances. You need the right type for what you want to check.
Can I measure EMF with my phone?
No. Phone apps use the phone's compass sensor, which can't measure radiofrequency and isn't calibrated for low-frequency fields.
What's the easiest way to reduce EMF at home?
Distance. Move the router away from bedrooms and seating areas, and keep your phone off your body and away from your bed at night. These cost nothing and usually make the biggest difference.
This article is an introduction to electromagnetic fields in the home. It does not make health claims. UK and international health bodies do not consider harm to be established at exposure levels below international guidelines.