UV Water Treatment - Virus Barrier
There are a variety of viruses that may be present in water that, if not treated, may present a health risk to consumers. Examples include adenovirus, rotavirus,poNovJrus. and coxsackievirus.
Health effects from different viruses vary, but the most common health effect is gastrointestinal illness. In some cases, depending on the specific virus, severe flu-like symptoms, meningitis, pneumonia, or other non-specific febrile illnesses have been observed. Small children are particularly susceptible to virus infection.
The United States Environmental Protection Agency’s Long Term 2 Enhanced Surface Water Treatment Rule (LT2) defined UV dose requirements for inactivation of viruses based on a relatively resistant virus: adenovirus. The UV dose required to accomplish a 4-log (99.99%) inactivation of viruses is 186 mJ/cm2 as seen in the USEPA UV Disinfection Guidance Manual. The LT2 Rule requires virus treatment for unfiltered public water systems and systems that utilize uncovered finished water storage reservoirs. Further, the USEPA’s Groundwater Rule requires that groundwater systems provide 4-log inactivation of viruses or demonstrate through monitoring that source waters are free from fecal indicators.