EMF Blankets: Do Faraday Blankets Work, and How to Test One

An EMF blanket is a throw or blanket made with a conductive fabric layer, usually silver or copper, that reflects and absorbs radiofrequency (RF) signal when it sits between you and a device. It does work as a shield in that limited sense, and you can check it in a few minutes with an RF meter. What it can't do is block low-frequency magnetic fields from wiring, or shield you from a source it isn't positioned between. This guide explains what a Faraday blanket does, how to test one, and what to look for before you buy.

Why are people asking about EMF blankets now?

Interest in personal shielding tends to rise whenever wireless exposure is in the news, and it is in the news this autumn. On 17 September 2026 the US Department of Health and Human Services opened a public request for information on electromagnetic fields and wireless radiation, which specifically lists phones, Wi-Fi, 5G, smart meters and wearable devices. The FCC opened a narrower consultation at the same time, and both close for comments on 21 and 22 October.

These are consultations, not findings, and they don't change UK exposure limits, which follow ICNIRP guidelines. But they have prompted a lot of people to look at the devices they hold closest — laptops on laps, phones and tablets in bed — and that is exactly where a blanket is used.

What is an EMF blanket made of?

Our own Anti-Radiation™ XL Silver Cotton EMF Blanket uses silver-plated nylon fabric on one face and 100% organic cotton on the other, with nothing in between, at 190 × 140 cm. You can see all current options in our EMF blankets collection.

Do EMF blankets actually work?

They work as RF shields in a specific, measurable way: a conductive layer between a transmitter and a meter reduces the reading on the far side. That is the same principle as a Faraday pouch or a bed canopy. Three conditions decide how much difference you see.

Position matters more than material

A blanket only shields what it sits between. Laid over your lap with a laptop on top, it is between the laptop and your legs. It is not between you and a router across the room, or a mast outside the window. A shield that is in the wrong place does nothing useful, however good the fabric.

Coverage and gaps

RF goes round edges. A small blanket on a large person, or one that is bunched up, leaves paths for signal to reach you. Bigger, flatter coverage gives more consistent results.

Frequency

Shielding performance changes with frequency. A figure measured at 1GHz doesn't tell you much about Wi-Fi at 5GHz. Look for attenuation stated in dB at named frequencies, ideally covering 2.4GHz and 5GHz Wi-Fi and the 3.4–3.8GHz band most UK 5G uses.

What can't a Faraday blanket do?

• It won't block low-frequency magnetic fields from wiring, transformers, chargers or power lines. Thin conductive fabric has very little effect on these at 50Hz.
• It won't shield a whole room. For signal coming from outside, a bed canopy or window treatment is the more appropriate tool.
• It won't stop the device transmitting. A laptop on top of a blanket still transmits normally upwards and sideways. The blanket simply sits between the device and you.
• It shouldn't be wrapped around a charging or warm device. Laptops need their vents clear, and tightly wrapping electronics in fabric can trap heat.

How do you test an EMF blanket at home?

You need an RF meter that covers the frequencies of the device you are testing. Our RF detectors covering 200MHz to 8GHz handle Wi-Fi, Bluetooth and UK mobile bands.

1. Set up a steady source. A phone streaming a video over Wi-Fi, or a laptop downloading a large file, gives a fairly constant signal.
2. Take a baseline. Hold the meter where your body would be — under the laptop, for example — and note the peak reading over 30 seconds.
3. Add the blanket. Place it between the device and the meter, in the way you would actually use it. Take the reading again in the same spot.
4. Test the edges. Move the meter towards the edges of the blanket to see where the signal leaks round.
5. Repeat a few times. Wireless signals fluctuate, so compare several readings rather than one.

A good conductive blanket should produce a clear, repeatable drop directly behind it. If you see no change at all, the blanket isn't doing what it claims. A quick sanity check for any Faraday fabric: wrap a phone fully in it and try calling the phone. If the call connects easily, the fabric is weak or the wrap has gaps.

What about grounded EMF blankets?

Some blankets, including ours, have a snap connector and a lead that plugs into the earth pin of a UK socket. This connects the conductive face to earth. It's important to separate two things:

• The RF shielding works whether or not the lead is connected, because it comes from the conductive fabric itself.
• The grounding connection is an optional feature. Always test that the socket is correctly earthed with a socket tester first, never connect to anything other than a correctly earthed socket, and ask a qualified electrician if you are unsure.

We describe what the grounding connection does electrically. We don't make claims about health outcomes from grounding, and you should be cautious of any seller who does.

How to choose an EMF blanket

• Size: big enough to cover your lap and torso when you use a laptop or tablet. 190 × 140 cm suits most adults and sharing on a sofa.
• Construction: a continuous conductive layer that reaches the edges.
• Tested figures: attenuation in dB at named frequencies.
• Care: conductive fabrics need gentle washing — cold or lukewarm, no fabric softener or bleach, air dry — or performance drops over time.
• Use case: lap and bed use suits a blanket. Room-level concerns suit a canopy, curtains or shielding fabric.

Frequently asked questions

Do EMF blankets block 5G?

A conductive blanket reduces RF across a range of frequencies, including the 3.4–3.8GHz band most UK 5G uses, when it sits between you and the source. It won't affect a mast signal that reaches you from a direction the blanket doesn't cover.

What's the difference between an EMF blanket and a Faraday blanket?

They are usually the same thing. "Faraday blanket" refers to the shielding principle — a conductive layer that reflects and absorbs RF — and "EMF blanket" is the more common retail name.

Can I use an EMF blanket with a laptop?

Yes. Place it between your body and the laptop, silver or conductive side facing the device, and keep the laptop's vents and fan outlets clear.

How do I wash an EMF blanket?

Follow the label. For silver fabrics that usually means hand washing in cold or lukewarm water, no bleach or fabric softener, and air drying. Harsh washing damages the conductive fibres.

Does an EMF blanket need to be plugged in?

No. The shielding comes from the fabric. A grounding lead, where supplied, is optional and should only be used with a tested, correctly earthed socket.

See the difference for yourself

The best way to judge any shielding product is with a meter in your hand. Browse our EMF blankets, pair one with an RF detector, and test it in the way you'll actually use it.

This article describes the measurable RF shielding behaviour of conductive blankets and how to test it. It does not make health claims, including about grounding. UK and international health bodies do not consider harm to be established at exposure levels below international guidelines. Reducing exposure is a personal choice. The US consultations referred to above are ongoing and have reached no conclusions.