Ultra-Violet (UV) light is invisible to the human eye and is divided into UV-A, UV-B and UV-C.
UV-C is found within 100-280 nm range. In the graph can be seen that germicidal action is maximized at 265 nm with reductions on either side. Philips Low pressure UV-C lamps have their main emission at 254 nm where the action on DNA is 85% of the peak value and 80% on the IES curve. As a result, our germicidal lamps are extremely effective in breaking down the DNA of micro-organisms. This means that they cannot replicate and cause disease.
Micro-organisms effective resistance to UV light varies considerably. Moreover, the environment of the particular micro-organism greatly influences the radiation dose needed for its destruction.