Proposal to establish uniform provisions concerning the approval of M₂ and M₃ special purpose vehicles designed specifically for the carriage of children to assist in the prevention of children being left inside. The regulation applies to vehicles of categories M₂ and M₃, class B and III. Vehicles shall be equipped with a physical inspection system that engages when the vehicle master control switch is turned off and generates an external visual and audible warning if not disarmed within 3 minutes for buses or coaches not exceeding 22 passenger seats, or within 5 minutes for those exceeding 22 passenger seats. The physical inspection system shall not influence the bus or coach’s performance or safe operation, and failure of the system shall not affect safe operation of the vehicle.