Scaffolding; roof safety systems of metal being temporary structures of metal for safety purposes; safety rails, guard rails, handrails and barriers; ladders, trestles, platform ladders; anchor points of metal; walkways of metal; overhead rails; karabiners and clips of metal; brackets including ladder support brackets of metal; line tensioners; common metals and their alloys; metal building materials; metal roofing materials and roof coverings including roof hatches of metal; non-electric cables and wires of common metal; small items of metal hardware; pipes and tubes of metal