This Standard specifies requirements for building maintenance units and supporting structures, permanently provided for use and which incorporate power-operated suspension equipment. It does not include requirements for suspended scaffolding.It is complementary to AS 1418.1, but the requirements specified herein shall take precedence over the corresponding requirements given in that Standard.NOTE: Guidance on the safe use of building maintenance units is provided in AS 2550.1.The provisions of this Standard shall apply to building maintenance units Types A, B and C (refer to Clause 1.5), unless stated otherwise.