This International Standard defines basic terms and specifies safety rules for overhead electrical monorails for materials handling, including the tracks, supporting structure, lifting and lowering devices, the trolleys and the load-supporting devices. It does not apply to systems driven by hand or by gravity, or to systems for conveying people, or to overhead conveyors. It does not apply to systems driven by hand or by gravity, or to systems for conveying people, or to overhead conveyors.