This case is of a changing room before the direct access to a clean environment dedicated to packing under modified atmosphere in a food industry (ham manufacturer) . The coverage area of each rrom is about 2×4m. and is used as for changing clothes for operators. Main requiremetn is to clean up operator’s shoes stopping viable contamination right in the changing room where operators wear disposable clean garments mandatory to safely access to restricted and clean manufacturing areas. Onto the blue mat all residues, dirt, powders etc. stay fixed until next washing cycle will take place