Manufacture of fire extinguishers and other equipment for projecting, dispersing or spraying liquids or powders whether or not hand-operated, including sand blasting machines, stream cleaning machines etc.
Manufacture of jewellery of gold, silver and other precious or base metal metal clad with precious metals or precious or semi-precious stones, or of combinations of precious metal and precious or semi-precious stones or of other materials
Interior completion such as ceilings, wooden wall coverings, movable partitions etc. ; Laying of parquet and other wood floor coverings, carpets and linoleum, wallpaper; tiling with ceramic, concrete or cut stone ceramic etc.
Operation of sand or gravel pits, basalt / porphyry, clay (ordinary), crushing and breaking of stone for use as a flux or raw material in lime or cement, manufacture or as building material, road metal or ballast and other materials for construction