What is FIR (far infrared rays)?
Far Infrared Rays (FIR) are energy rays from the Sun. FIR rays are part of the part Electromagnetic Spectrum with a wavelength longer than visible light, but shorter than microwave radiation. The name Far Infrared means “below red” (from the Latin infra, “below”), red being the color of visible light of longest wavelength. Far Infrared electromagnetic radiation has the longest wavelengths in the infrared region, between approximately 50 and 1,000 micrometers.
