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Why Aluminium Foil Blocks Radiation?

Jul. 22, 2020

Yes, aluminium foil acts as an aluminium mesh to block most wavelengths of RF radiation. 

Next, the aluminium foil supplier will take a closer look at it and find out how and why aluminium foil blocks radiation.

Does aluminium foil protect against RF radiation?

Aluminium foil does block or shields against RF waves. As aluminium is a conductor of electricity, it forms a barrier commonly known as a miniature Faraday cage, thus blocking radio waves altogether.


You can try this yourself. Obtain a large piece of aluminium foil, lay it flat, place the phone on top and wrap it around. Now try to make a call and the phone will have no signal whatsoever. These radio waves are a form of EMF radiation. The aluminium foil acts as a barrier, blocking those waves completely.

Aluminium Foil


If you've heard of a miniature Faraday cage before, it's really just a structure, usually made of a wire mesh-like aluminium, that completely blocks radio and microwave radiation.

The thickness of the metal is irrelevant; an ultra-thin aluminium foil is just as good as a thick, heavy sheet of metal. The important factor is that there are no holes larger than the shortest wavelength of the radio or microwave trying to get in.


Take a look at your microwave oven. Almost every microwave window has a subtle layer of metal mesh. This is a miniature faraday cage-like material, such as aluminium, which is so small that microwave radiation cannot be emitted. Aluminium foil can be used well for these purposes, but a better option is an aluminium shield. This shielding will effectively block RF radiation and microwave radiation.


However, you do need to remember that although aluminium does block EMF radiation, it will not absorb it. RF and microwave EMF radiation travels in a straight line. Therefore, you are only protected if you have a material that directly blocks the radiation between you and the radiation source.

If you have wifi or devices that emit radiation, make sure you are careful with materials such as EMF protective paint or aluminium, as these waves will only bounce around and will be accelerated and amplified. A better use for aluminium mesh and EMF protective paint is to keep RF waves out of your house, for example, to reduce the surrounding EMF radiation from local cell towers coming into your house. It can be seen that aluminium foil, or in this case aluminium mesh, with holes small enough to block wavelengths, is very effective at shielding or blocking EMF radiation.

How to test if aluminium foil blocks radiation

The best way to do this is to get a good quality EMF meter. Not only can you test to see if aluminium foil or other EMF radiation shielding materials are working well, but you can also use it for a huge range of other personal protection.

Ways to use aluminium foil to block EMF radiation

1. Turn off your WiFi

Take a few sheets of aluminium or copper foil and create a cage so that the bottom is large enough to cover your home router. Now slide a piece of foil under the router. Then place the cage you have created over the router to create a mini Faraday cage. The foil will completely block the WiFI signal and eliminate EMF radiation. This works very well at night when people are sleeping and don't need wifi.

Although, a better option is to just get router protection, which will block most EMF radiation while still allowing you to use WiFi.

2. Create a mini miniature Faraday cage for electronics

Take an unused shoebox or cardboard box and completely line the inside with aluminium foil. Use tape, glue or adhesive to avoid making holes in the box. You will create a mini miniature Faraday cage. Use it to block signals from electronic devices when you're not using them, or to put your family's phone in during the family game night.

3.Other EMF blocking metals

Aluminium foil is really cheap, efficient and works very well for DIY projects at home. There are other metals that work well for this purpose and for creating a miniature Faraday cage. The other two metals you will most often see are steel. This is why you usually encounter all sorts of dead spots in buildings with a significant steel structure that do not receive mobile phone signals. Another material that works similarly to aluminium foil in terms of blocking radiation is copper.

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