Infrared heating is often misunderstood because the term “infrared” covers a broad range of wavelengths, each with very different characteristics and applications. This can lead to confusion around safety, comfort, and suitability for heating buildings.
Infrared radiation is divided into three main categories based on wavelength position within the electromagnetic spectrum . In simple terms, the longer the wavelength, the gentler and more evenly distributed the heat tends to be.
Near Infrared (NIR)
Near infrared sits closest to visible light on the electromagnetic spectrum and operates at relatively short wavelengths. Because of this, near infrared produces very high surface temperatures and often emits a visible red or orange glow.
Near infrared is commonly used in industrial and technical applications such as curing, drying, manufacturing processes, fibre optics, and medical equipment. It is also the form of infrared used in devices like remote controls and night-vision technology.
Due to its intensity and high operating temperatures, near infrared is generally not suitable for heating occupied indoor spaces over long periods.
Mid Infrared (MIR)
Mid infrared occupies the middle range of the infrared spectrum and produces moderate heat intensity. It penetrates materials more deeply than near infrared, but less deeply than far infrared.
Mid infrared is used in specialist heating applications, certain industrial environments, and some therapeutic or short-duration heating scenarios. It typically operates at higher surface temperatures and may emit visible light.
While mid infrared can deliver rapid warmth, it is less commonly used for continuous indoor space heating due to comfort considerations and operating characteristics.
Far Infrared (FIR)
Far infrared has the longest wavelengths within the infrared spectrum and produces a gentle, evenly distributed form of radiant heat. Unlike near and mid infrared, far infrared does not emit visible light and operates at much lower surface temperatures.
Far infrared is the wavelength range most commonly used for residential and commercial infrared heating systems. It works by gently warming surfaces and occupants within a space, which then re-radiate heat back into the room.
Because far infrared does not rely on heating the air directly, it can perform effectively in buildings with high ceilings, intermittent use, or areas affected by draughts. This makes it particularly suitable for homes, offices, heritage buildings, and commercial spaces.
Which Type of Infrared Is Used for Heating Buildings?
For indoor space heating, far infrared is the most appropriate and widely used option. Its longer wavelengths allow heat to be absorbed efficiently by surfaces and people, creating stable and comfortable conditions without the intense surface temperatures associated with shorter wavelengths.
To understand how this applies in practice, you can explore how far infrared heating systems work and why they are used in a wide range of real-world environments.
Need Further Advice?
If you have any questions about infrared wavelengths or would like guidance on selecting the right heating solution, please visit our FAQs or contact our technical team.
You can also speak directly to one of our specialists by calling 01204 520544 or emailing info@infraredheatingsupplies.com.
