|UV-Disinfection-Equipment requirements according to
the german DVGW:
|The effective disinfecting UV-radiance can only be ascertained with the help of microbiological tests. It can neither be specified actinometrically nor physically.
|According to the DVGW-guidelines, an effective disinfecting UV-radiance of at least 400 J/m² is required to achieve an efficient disinfection. This should be tested with a test-organism under ideal conditions with a homogenous radiance of 400 J/m² which shows a reduction of at least 99,99 % and 4 log-range respectively.
|At present there isn‘t any known test organism which meets these ideal conditions. Tests are made with 2 different resistant organisms, Escherichia coli and spores of Bacillus subtilis
until an adequate organism is found. With B. subtilis it can be proven that a radiance of 400 J/m² is reached but only at a reduction rate of approximately 2 log-range.
| In a reduction of at least 6 log-range it can be proven with e. coli if there is a decrease of disinfection due to insufficient irradiated volumetric content.
|A disinfection-equipment according to DVGW-guidelines has to be certified if disinfected drinking water is inducted into the drinking water system. A certification is not necessary with drinking water purification systems if drinking water is not inducted into the system.
|A WaterVitt-equipment was tested with the collaboration of the University of Applied Sciences in Wiesbaden (MND Environmental Technology faculty) in view of its use in drinking water areas. Degermination of Escherichia coli and Bacillus subtilis was good to very good. And even in artificially blurred water a good disinfection-efficiency was achieved..
|Currently there are test-equipments running at Osram and Siemens. The equipment went into serial production end of August 2003.The projects partners estimate great market potential in non-corporate as well as industrial areas but especially in Third World countries.
|A UV-disinfection-equipment with 3 lamps (120 W) and a flow-rate of 6 l/s is currently being tested for drinking water purification in Austria and the community Reichramig. A preliminary permit was granted to induct the water into the drinking water system due to the outstanding disinfection-efficiency.
|The German TÜV (= German Association for Technical Inspection) test certificate is already initiated. The next step is to certify the equipment according to the guidelines of the German DVGW (German Association for Gas- and Water-Compartment).
|Extensive inquiry report of the University of Applied Sciences in Wiesbaden (Download PDF File)