Does Concrete Block EMF Radiation?

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 cuts down on sunlight, your walls reduce sound, and the lead vest at the dentist blocks X-rays. In the same way, materials like mylar, copper, and aluminum can reduce EMF radiation by absorbing or scattering the photons that pass through them.

In other articles, I’ve also explained the inverse-square law, which says that doubling your distance from a radiation source reduces your exposure to a quarter of the original level.

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:

1. The attenuation is completely dependent on how thick the concrete is.
2. The attenuation of concrete increases with higher frequencies.

Since the EMF radiation-blocking capabilities of the concrete are 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

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.

Concrete Blocks

Again, concrete blocks were about the same but 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:

I do hope you found the answer you were looking for in my post “Does Concrete Block EMF Radiation,” If you did, please consider sharing it!