As applied to protective ensembles: Any material, part, or subassembly used in the construc¬tion of the protective ensemble or any element of the protective ensemble. NFPA 1971, 2000 ed. As applied to fire and emergency services: Any material, part, or sub-assembly providing the required protection that is used in the construction of the SCBA. NFPA 1981, 2002 ed. As applied to fire apparatus maintenance: A constituent part of a mechanical or electrical device. NFPA 1915, 2000 ed. As applied to fire apparatus refurbishing: A con¬stituent part of a fire apparatus or system. NFPA 1912, 2001 ed