First, to answer the question “does concrete block EMF radiation?” the answer would be no, it does not block EMF Radiation. However, concrete will attenuate (or reduce) the amount of radiation that passes through it.
Let’s get into this in a bit more detail.
How Does Concrete Reduce EMF Radiation?
So when you’re trying to understand how a material blocks, shields, or reduces EMF radiation, try not to think of it in absolute terms. Rarely is it the case that a material completely blocks EMF radiation, instead it typically reduces the radiation, which is called attenuation. In physics, attenuation is the gradual loss of force as energy passes through a material.
For example, tinted glass attenuates sunlight, the walls of your house attenuate sound, and the lead vest you wear at the dentist attenuates the x-rays. Materials like mylar, copper, aluminum, attenuate EMF radiation by absorbing or scattering the photons as they pass through. I’ve talked in other articles a bit about the inverse-square law, which essentially means that as you double your distance from a source of radiation, you quarter your exposure to it.
So when calculating how much EMF Radiation you’re being exposed to, you have to look at both the attenuation of materials between you and the source, as well as your distance from it.
So when we’re looking at shielding materials, in this case, concrete, we want to think about how much the radiation is being reduced. This attenuation is measured in decibels (dB). If you look at the chart below, you can get an idea of how much radiation is blocked at various decibel levels.
How Do We Know How Much EMF Radiation Concrete Reduces?
So in 1997, the National Institute of Standards and Technology (NIST) published a paper called “Electromagnetic Signal Attenuation in Construction Materials,” which is completely open to the public, just google it.
They did not do this testing because of the inherent dangers of EMF radiation, but instead to better understand how wireless control systems would be affected by various building materials.
So let’s get to the main question:
Does Concrete Block EMF Radiation?
By now you probably know that, no, concrete certainly does not block or shield EMF radiation completely, but it does reduce it quite a bit.
So when NIST tested how well concrete attenuated EMF radiation, they found the following:
- The attenuation is completely dependent on how thick the concrete is.
- Attenuation of concrete increases with higher frequencies.
Since the EMF Radiation blocking capabilities of the concrete is completely dependent on the thickness, the more concrete you have between you and the source the lower the radiation will be. So if you have a concrete wall that was attenuating (or shielding) at 10 dB and then you tripled the thickness of that wall, you’d be shielding at 30 dB.
Reinforced concrete with rebar or a steel mesh attenuated the radiation at almost the same rate when NIST tested it as you can see from the chart below.
Again, concrete blocks were about the same but actually were slightly worse at attenuating the radiation since the blocks had holes which reduced the overall thickness.
If you’re looking to reduce the overall amount of EMF radiation you’re exposed to, here is where you should start:
Basics of EMF Protection
Step 1 is reducing the amount of radiation in your life, for that, I would start by reading the following articles:
A Non-Tinfoil Guide To EMFs (This one does cost a few dollars, but is a fantastic book)
If you’ve been able to make it through some of these, you should have some good knowledge on how to reduce your overall exposure to radiation. If you didn’t make it through, here are a few of my absolute favorite tips:
- Turn your mobile phone off at night, or if you must use it for an alarm (i’d suggest a simple mechanical alarm clock) then at least put it in airplane mode.
- Try to use Ethernet connections to your computers whenever possible instead of WiFI
- Get rid of your microwave.
- Reduce your exposure to your Smart Meter, check out that article for all the information you should need
- Reduce your use of tablets and smartphones.
- When using your cell phone, try to use speakerphone or headphones, try to not put your cell phone right up to your head.
There are way more tips than I can list here, so check out some other articles on EMF Academy for more great tips and help!