DIN 19643-2
DIN 19643-2 Treatment of water of swimming pools and baths - Part 2: Combinations of process with fixed bed filters and precoat filters
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/2012
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 11/01/2012