Ultraviolet disinfection

UV disinfection is a physical process that inactivates viruses, bacteria and protozoa by the emission of UV light, at germicide wavelengths, which cause irreparable cell damage.

Ultraviolet disinfection (UV) does not inactivate microorganisms by chemical interaction, but the inactivation occurs by absorption of UV light, which causes a photochemical reaction in the microorganism, which damages nucleic acids and other vital cellular components, causing irreparable harm or death of exposed pathogens. The most powerful wavelength to damage DNA and RNA is approximately 254 nm.

The facilities consist of one or more ultraviolet lamps installed inside protective quartz tubes in contact with water. As it is a physical disinfectant, which doesn't leave residues in water, it should only be used followed by a secondary chemical disinfectant to prevent the system from the growth of microorganisms and formation of biofilm. The most common point of application of the ultraviolet radiation is at the final stage in the treatment process, just before the distribution system and after filtration.