The product use the cold cathode ultraviolet tube. The ultraviolet ray of 253.7 nms which send out by the tube can be easily absorbed by the protein and nucleic acid of germs and virus. It will destructed the dna structure of the protein and nucleic acid and cause the germs and virus dead. There are more than 18 kinds of germs and virus can be killed in this way. For example: the escherichia coli, bacillus, escherichia, klugvera, m.Tuberculosis, neisseria, salmonella, aspergillus.Niger, penicillium, mucoralas, stool funmgus, hepatitis virus, influenza virus, policvirus etc..