Keywords: Copper; Copper alloys; Pipes; Seamless pipes; Gas pipes; Water; Fluid equipment; Water heaters; Hot-water supply systems; Heating equipment; Water supply and waste systems (buildings); Water supply (buildings); Cold-water supply systems; Pipework systems; Waste-water drainage; Sanitary appliances; Drainage; Dimensions; Dimensional tolerances; Mechanical properties of materials; Designations; Defects; Conformity; Quality control; Test methods; Marking; Sampling methods