Understanding UV Wavelengths

UV light is a naturally occurring electromagnetic radiation.

It accounts for 10% of the light emitted by the sun.

The wavelengths of UV light are shorter than those of both visible light and infrared light, ranging between 100 nano-metres (nm) and 400 nm.

Based on wavelengths, UV light is further broken down into three sub-bands:

UV-A (315 nm to 400 nm),

UV-B (280 nm to 315 nm), and

UV-C (180 nm to 280 nm).

Disinfecting Wavelengths

UV-C light which represents UV wavelengths below 290nm, is a weak ultramagnetic radiation, and gets blocked / absorbed by the ozone layer in the Earth's atmosphere, so it does not naturally reach the planet’s surface.

The most effective germicidal wavelengths occur between 200nm and 280nm. For this reason, this sub-band of UV-C light has come to be known as UVG (Ultra Violet Germicidal) and due to the application process by Irradiation, the method is referred to as UVGI (Ultra Violet Germicidal Irradiation).