Earthing and EMF: what it does and what it does not

Around every socket, every charger and every cable in your wall sits an alternating electric field. You notice nothing of it, but your body picks it up: voltage builds on your skin. That is not theory or estimation, it is something you can read off an ordinary multimeter. And it is exactly the part that earthing measurably changes.

A great deal is claimed about this subject and very little is measured. So below is what has actually been recorded, with the numbers, and just as clearly what earthing does not do.

What sits on your skin

Set a multimeter to AC voltage, hold one probe between your fingers and push the other into the ground outside. In an average bedroom you read a few hundred millivolts, sometimes a few volts. Stand right beside an extension lead or a desk lamp and the value goes up.

That voltage comes from the wiring in your walls, not from your appliances. It is there even when everything is switched off, because no current needs to flow to create a field. That is why the head of your bed is often the spot with the highest value: switches, a lamp, a charger and an alarm clock all come together there, in the place where you lie for eight hours.

What earthing does about it

The moment you are connected to earth, that charge drains away and the value drops to almost zero. It is the same measurement as above, only with the connection plugged in. It happens within seconds and you watch it happen live as you push the plug in.

How large that difference is has been measured independently several times. Independent measurements come out at a drop of a factor twenty to ninety, depending on how much equipment is switched on and how the room is wired.

The weightiest publication on this comes from neonatology. In 2017 Passi and colleagues recorded it in twenty-six premature babies in intensive care: skin voltage fell by about 95 percent as soon as the earthing was connected, from 415 to 19 millivolts, and vagal tone rose by 67 percent. Published in Neonatology, volume 112, pages 187 to 192.

That study carries weight for two reasons. Newborns have no expectations about what earthing ought to do, so a placebo effect is ruled out. And an intensive care unit is full of equipment, so it is precisely the environment where this type of field is strongest.

What earthing does not do

Earthing works on the charge that builds on your body. It removes what the wiring around you puts on your skin. It goes no further than that.

It is not a shield and not a filter. The Wi-Fi signals in your house still cross the room, your phone transmits and receives exactly as before, and the mast down the road notices nothing. Those are high-frequency signals and they behave differently from the low-frequency field this is about.

Anyone selling you a product that protects against radiation is selling you something other than what we sell. We sell a connection to earth, and the only thing that measurably changes because of it is the voltage on your skin.

What does lower your exposure

If it is the fields themselves you care about, rather than the charge on your body, then this works:

• Distance. A field falls off quickly the further away you are. A charger a metre away instead of beside your pillow makes more difference than any product.
• Unplug it. An appliance that is switched off but still in the socket keeps the field in the cable alive. Pulling the plug does not.
• Wired where you can. A fixed connection to your desk or your television does not transmit.
• Aeroplane mode at night. Costs nothing and covers eight hours.
• Have it measured. If you really want to know, a building biologist measures low and high frequency separately, with equipment that goes far beyond a multimeter.

That list sells you nothing. It is there because it is true.

Where earthing gives you the most

The bedroom, for two reasons. You lie there longest at a stretch, and it is the room where most people unknowingly have the most appliances right beside their head.

In practice you start there with the sheet, the sleeping mat or, as the smallest step, the pillowcase. If you work at a screen all day, the desk mat under your forearms is where you measure the difference during the day.

If there is no earthed socket in the room, it can still be done with an earthing rod or an alligator clip. Both are covered in earthing without an earthed socket.

Measuring it yourself

You do not have to take our word for it, and that is exactly the point of this article. A twenty euro multimeter is enough.

Set it to AC voltage on a two volt range. Hold one probe between thumb and forefinger. Push the other into the earth pin of an earthed socket, or use an alligator clip on a bare heating pipe. Take the reading. Then connect your earthing product, lie or sit on it, and read again.

If you see the value drop from hundreds of millivolts to tens or lower, your set-up works. If you see no difference, something is loose or the socket is not earthed.

How the connection is put together technically, and why current can never run through your product, is in earthing: safe and effective. All the studies on earthing, with year and number of participants, are lined up in scientific evidence for earthing.

Earthle does not sell medical devices and does not replace treatment. If you have symptoms, take medication, are pregnant or have an implant, speak to your doctor first.