UV air recirculators UVR-M and UVR-Mi are equipped with bactericidal lamps (Philips). The main point of the test was to examine the UV-light irradiation impact on various microorganisms types. UVR-M and UVR-Mi, UV air recirculators Test Report For majority of microorganisms the energy needed for deactivation was investigated and reported by UVP Inc. Depending on this data it is possible to determine the effectivity of UV air recirculators produced by BioSan Ltd. Throughout knowing the energy produced by instrument and comparing it to energy needed for microorganism deactivation. UVP table is presented below as well as results of measurements performed at BTC laboratory. Bacteria destruction chart Amount of germicidal, shortwave (254 nm) ultraviolet energy necessary for complete destruction of various organisms. Presented by UVP inc. Medical–Biological Research & Technologies Bacteria organisms Energy: mW seconds per cm 2 Other microorganisms Energy: mW seconds per cm 2 Bacillus anthracis 8.7 S. enteritidis 7.6 B. Megatherium sp. (veg.) 2.5 B. Megatherium sp. (spores) 5.2 B. parathyphosus 6.1 B. subtilis 11.0 B. subtilis spores 22.0 List continues on the next page ... YEAST Saccharomyces ellipsoideus 13.2 Saccharomyces sp. 17.6 Saccharomyces cerevisiae 13.2 Brewer’s yeast 6.6 Baker’s yeast 8.8 Common yeast cake 13.2 List continues on the next page ... General information UV radiation affects the viability of microorganisms, as the absorbed radiation by the molecules leads to photochemical reactions in the structure of DNA/RNA. UV radiation causes adjacent pyrimidine molecules on DNA/RNA to dimerise. Pyrimidine dimers block the reproduction of bacteria. If bacteria can’t reproduce, it dies. Photochemical reaction The formation of pyrimidine dimers; as an example taken thymine (source http://www.photobiology.info/) T T N N N N N N N N UV PR CH 3 CH 3 CH 3 CH 3 O O O O O O O O TT UVR-M UVR-Mi UVR-M and UVR-Mi, UV air recirculators Test Report source: www.uvp.com