Step-by-Step: 3 Simple Faraday Containers

The hardest part about protecting your equipment is simply doing it. A few rolls of heavy duty aluminum foil, some cardboard boxes and a galvanized steel trash can are enough to create your own Faraday cage and protect your electronics from EMP.

The cardboard box

The simplest and cheapest way to build your own Faraday container is to use heavy duty aluminum foil, tape, and a cardboard box. By placing anything you want to protect in the box and then wrapping the whole thing in aluminum foil, you have the beginnings of an effective Faraday container. With heavy duty tape, tape down ever edge of tape, making sure that there are no open spaces between layers of foil or the foil and the box.

Once the box is thoroughly taped up, tape a list of the box contents to the top and then store it in an out-of-the-way location. If you are storing more than one of the same items, multiple walkie-talkies, for example, store them in separate Faraday containers, so if one happens to not be thoroughly sealed against EMP and its electronics are affected, you’ll have back-ups.

The Mylar EMP bag

Another simple way of creating a Faraday container is to simply use very heavy duty Mylar bags, specifically designed to protect against the invisible waves of an electromagnetic pulse. We prefer the ones sold by Dr. Arthur T. Bradley on his website, and you can purchase those here.

He says, “With a PhD in electrical engineering, I was fortunate enough to have the equipment to test numerous brands of bags for their shielding effectiveness. The Dri-Shield 3400 series bags were shown to be superior to all others, providing approximately 50 dB of shielding across all relevant EMP frequencies (100 kHz to 1 GHz). That means they will reduce the electric field by at least 99.7%, reducing even a worst-case 50,000 V/m down to 158 V/m – a level that most electronics would survive.”

Dr. Bradley is a regular instructor at Preppers University, and we trust his judgement. We recommend listing the electronics you want to store and then going to his website to check out the different sizes of bags. It is safe to put more than one item in a single bag.

When your bag is ready to seal, fold the top over twice and seal with a strip of heavy duty tape, making sure it’s very tightly sealed. Write the contents of the bag on the outside with a Sharpie or tape a list of the contents to the outside of the bag. Numerous sealed bags can all be stored together in a plastic bin, a metal trash can, or any other container. This is more for convenience as the bags sold by Dr. Bradley are highly effective on their own.

The galvanized trash can

This third Faraday container is very easy to put together and is quite effective. It’s important that the trash can have a very tightly fitting lid.

You will line the bottom and sides of the can with cardboard. This can be done by tracing the bottom of the can on to cardboard, and then cutting inside the pencil line to create a circle just slightly smaller than the interior bottom of the can. Next, cut one long cardboard piece to the height of the can, and insert it into the can so it creates a lining.

Place your electronic items in the cardboard lined can and then place the lid on top. Make sure the lid of the can fits tightly. To be on the safe side, you can tape the lid closed with a couple of layers of tape. Again, be sure there isn’t even the tiniest gap between the tape and the lid/can.

For complete information about Faraday containers, be sure to watch the recorded webinar.