Radio Frequency (RF) Radiation

Radio frequency (RF) radiation refers to the band of the electromagnetic spectrum spanning roughly 3 kHz to 300 GHz. It sits below infrared light and above extremely low frequency (ELF) fields. The International Telecommunication Union (ITU) subdivides this band into ranges such as VHF, UHF, SHF, and EHF.

RF radiation is non-ionizing. The accepted dominant biological effect at exposures above regulatory limits is dielectric heating of tissue — the same mechanism a microwave oven uses to cook food, but at far lower intensities for consumer devices. Whether non-thermal effects exist at sub-limit exposures is an open scientific question; the World Health Organization and ICNIRP continue to review the evidence.

Everyday RF sources include Wi-Fi access points (2.4 GHz and 5 GHz bands, with Wi-Fi 6E adding 6 GHz), cellular base stations and handsets (sub-6 GHz bands and millimeter-wave 5G), Bluetooth (2.4 GHz), microwave ovens (2.45 GHz), and broadcast television and radio transmitters.

Exposure is typically expressed as power density (W/m²) for far-field conditions or as Specific Absorption Rate (SAR, W/kg) for near-field conditions where the body is close to the source. The FCC requires that consumer wireless devices be tested and certified to comply with SAR limits before sale.

Shielding RF radiation relies on conductive barriers — solid sheets or fine meshes of metal — that absorb and reflect the incident wave. Effectiveness depends on the conductivity of the material, its thickness, and, for meshes, the size of the apertures relative to the wavelength.

RADIHALT designs EMF protection blankets built around woven copper-nickel Faraday fabric. The terminology on this page — from Faraday-cage physics through attenuation figures and ICNIRP exposure limits — is what underpins the engineering and the claims we publish about our products.

We try to keep our marketing language tied to the same vocabulary regulators and physicists use. If a definition on this page conflicts with anything on a RADIHALT product page, the glossary entry is the source we hold ourselves to.