This Standard sets out requirements and provides guidance for the installation, maintenance, testing and replacement of sealed secondary batteries (either valve-regulated or gastight) permanently installed in buildings, structures or premises. This Standard covers secondary batteries with a nominal voltage of 24 V or greater, and a capacity exceeding 10 A.h at the 1 h rate. It includes batteries comprising lead-acid cells and alkaline cells (such as nickel-cadmium cells). This Standard covers requirements for components of the d.c. system of which the battery is a part, where these components comprise an essential part of the d.c. system. This Standard covers sealed cells only. The installation and maintenance of vented cells are covered by AS 3011.1 and AS 2676.1.