These lamps have the shortest UV wavelengths (between 200-280nm) and as a result are potentially the most harmful. Accordingly, extra care should be taken when handling and using these types of UV lights. The type of UV radiation these bulbs emit targets the DNA of microorganisms, causing cell death or making reproduction impossible. They’re certainly not the type of bulbs to be used in the home. They’re mainly used in professional and industrial environments in processes such as water treatment, disinfection, sterilisation and food sanitation. Germicidal UVC lights are commonly sold as tubes, either straight or turned into more compact shapes. Unlike the UVA lamps, germicidal tubes are usually transparent.