In this study, clay composites were subjected to electromagnetic transmission testing at frequencies in the region of non-ionizing radiation. Specimens were made with partial substitution of clay with different admixtures by mass. Admixtures used were Fly Ash, four different particle sizes and phases of Titanium Dioxide (TiO₂), Zinc Ferrite (ZnFe₂O₄), Maghemite (γ-Fe₂O₃) and Antimony Tin Oxide (ATO). The additives were thoroughly (chemically, structurally, morphologically) characterized. The replacement percentage was 5 wt.%. Electromagnetic transmission assessment included S₂₁ transmission coefficient measurements for samples with different additives. The lowest transmission was reported for the clay specimens with ATO and Titanium Dioxide, especially at higher frequencies. A decrease in the transmission parameter with increasing specimen thickness was also confirmed.

Electromagnetic radiation plays a crucial role in everyday human life. Mobile devices, 4G, 5G networks, Wi-fi, radars, audio devices, wireless devices are just a small part of the sources with which man is in almost every moment surrounded. The benefits of using artificial sources of electromagnetic radiation are unquestionable, but even today not enough is known about the potential harmfulness of long-term exposure to these radiation sources. For this reason, scientists are trying to find the most effective ways of protection using various coatings, concrete and clay composite elements, fabrics, etc. In this study various methods for electromagnetic radiation shielding measurements were explained. Study presents experiment set-ups, specimen dimensions, recommended frequency ranges and recommendations when to use each method.

The increasing exposure to non-ionizing electromagnetic (EM) radiation driven by urbanization and digitalization has encouraged the development of building materials with EM shielding properties. This study investigates the potential of enhancing the electromagnetic shielding properties of cement mortars by incorporating multi-walled carbon nanotubes (MWCNT) in various dosages (1%, 3%, 6%, 9% and 10% by binder mass). The microstructural and mechanical effects of MWCNT addition, as well as their efficiency in reducing EM transmission in the frequency range of 1.5–10 GHz (covering LTE, 5G, WiFi, and radar systems), were analyzed. S₂₁ measurements were performed using a modified coaxial transmission line method with a vector network analyzer. Results show that increasing the MWCNT content enhances EM shielding effectiveness but simultaneously affects the mortar’s microstructure and mechanical properties. Higher MWCNT levels achieved the best EM shielding, with an improvement of up to 27.66 dB compared to ordinary mortar in the navigation radar frequency range. These findings confirm the potential of MWCNT-modified mortars for protecting buildings and sensitive infrastructure—such a hospitals, communication hubs, data centers and military facilities—from EM radiation.

In today's modern world, artificial sources of nonionizing electromagnetic radiation have become an indispensable part of our lives. The issue of potential health risks from exposure to this type of radiation remains a topic of discussion among scientists. In this paper, the influence of brick firing and the increase in humidity in solid bricks on the results of protection against EM radiation is analyzed at frequencies from 1.5 GHz to 6 GHz. Wet brick has the greatest ability to attenuate electromagnetic radiation, while drying and firing reduce this protection. Results showed that adding moisture to the material increased the electromagnetic shielding, while firing resulted in decreased shielding. The results are in agreement with the literature, where the electrical conductivity of the material is a key factor in electromagnetic protection. This work provides additional understanding of the influence of moisture and firing on the electromagnetic shielding of materials, which can be useful for the design of load-bearing structural elements with high efficiency shielding from electromagnetic radiation.