UV-C light is germicidal - i.e., it deactivates the DNA of bacteria, viruses and other pathogens and destroys their ability to multiply and cause disease.
· UVA: sun tanning, testing, inspection, insect traps, stage effects, blacklight, phototherapy* (315-400nm)
· UVB: sun burning, inspection, analysis, testing, phototherapy* (280-360nm)
· UVC: germicidal (253.7nm), ozone producing (185nm)
UV-C light is germicidal - i.e., it deactivates the DNA of bacteria, viruses and other pathogens and destroys their ability to multiply and cause disease. Specifically, UV-C light causes damage to the nucleic acid of microorganisms by forming covalent bonds between certain adjacent bases in the DNA. The formation of such bonds prevent the DNA from being unzipped for replication, and the organism is unable to reproduce. The difference has to do with the ability of UV rays to penetrate body surfaces. UVC has an extremely low penetrating ability. It is nearly completely absorbed by the outer dead layer of the skin where it does little harm. It does reach the most superficial layer of the eye where overexposure can cause irritation, but it does not penetrate to the top of the lens of the eye and can not cause cataracts. UVC is completely stopped by the ordinary eye glasses and by ordinary clothing. In this method of disinfection, nothing is added which makes this process simple, inexpensive and requires very low maintenance. Ultraviolet purifiers utilize germicidal lamps that are designed and calculated to produce a certain dosage of ultraviolet (usually at least 16,000 microwatt seconds per square centimeter but many units actually have a much higher dosage.) The principle of design is based on a product of time and intensity - you must have a certain amount of both for a successful design.
