In 1877 scientists first observed strong sunlight disinfecting water. They noticed that sugar water kept in the shade went cloudy as microorganisms grew in it, whereas the sugar water kept in direct sunlight stayed totally clear. Being able to artificially create the correct wavelengths of UV light with lamps gives us the power to disinfect a variety of liquids as well as air and surfaces.
UV disinfection (also known as ultraviolet germicidal irradiation) is a chemical-free disinfection method that uses short-wavelength ultraviolet (UV-C) light to kill or inactivate microorganisms by disrupting their DNA, leaving them unable to perform vital cellular functions such as reproduction. At the 254nm wavelength UV light can penetrate the cell wall of a microorganism, permanently altering the DNA structure within seconds and leaving no chemical by-products as a result.
Precise and targeted ‘dosing’ is used to calculate the type of lamp needed for different applications and how long different liquids, air or surfaces need to be exposed to the UV light, in order for them to be safely disinfected.
Dosing takes into account the UV intensity being given out from the lamps, the UV transmittance (UVT) of the water, air or surface (if applicable) and the amount of time the substance being disinfected is exposed to the UV light.
