How Does UV Work as a Germicide?
Ultraviolet (UV) output emission having wavelengths in the spectral region 100 – 400 nmis extremely effective in killing micro-organisms such as germs, bacteria, viruses and molds. The UVC light is absorbed by the organism’s nucleic acids to create sterility, making it incapable of multiplying to infectious numbers. A cell that cannot reproduce is considered dead since it is unable to multiply to infectious numbers within a host. Lamps radiating in this ultraviolet region have been used with great success for air and water purification, protection of food and beverages, sewage treatment and similar applications. The most effective means of producing UV energy is through the use of a low-pressure mercury arc in which the mercury atoms are excited to a high energy level. Upon dropping back to a low energy, the atoms strongly radiate a characteristic spectral line having a wavelength of 254nm. By a fortunate coincidence, this wavelength is close to 265nm, the wavelength most deadly to mic
