Abstract ISO 15763 defines terms and specifies requirements and tests for vehicle alarm systems (VAS) intended for installation within buses and commercial vehicles (as defined in ISO 3833) having a maximum authorized total mass (code ISO-M08 defined in ISO 1176) of greater than 3,5 t. It is applicable to VAS designed to detect or sense, and to indicate, the unauthorized opening of a vehicle's doors, luggage-compartment lids, bonnet/hood and emergency exits, as well as the tilting of the driver's cabin and the disconnection of a trailer or of the power supply. It covers both VAS intended for installation as original equipment, and those intended to be installed after delivery of the vehicle