From 1 July 2013 all new School Buses in Australia must be fitted with a Child Safety Alarm system hardwired from the vehicle ignition circuit and powered from the vehicle battery. The system must activate after no more than five minutes of operation or immediately once the passenger door has been opened or closed, cannot be overridden by the operator, and can only be deactivated after the disabling switch is actioned. The disabling switch must be located inside the vehicle behind the rearmost passenger seats requiring the driver to walk to the rear to deactivate it. An audible alarm must sound when the engine ignition switch is turned off and the disabling switch has not been actioned, and must be audible from up to 10 metres distance.

The session agenda includes discussion of the current draft UN Regulation for buses and coaches including homework feedback, feedback on the proposal in GRE from the South Korea delegate, preparation for the 1–5 June 2026 GRSP meeting, and any other business.

Proposal to establish uniform provisions concerning the approval of M₂ and M₃ vehicles to assist in the prevention of children being left inside. This regulation applies to vehicles of categories M₂ and M₃ class B and III designed or equipped primarily for the carriage of children, or special purpose vehicles of categories M₂ and M₃ class B and III designed specifically for the carriage of children. Vehicles shall be equipped with a physical inspection system which satisfies the requirements, including that the system shall be engaged when the vehicle master control switch is turned off and shall generate an external visual and audible warning if not disarmed within three minutes for buses not exceeding 22 passenger seats, or within five minutes for buses exceeding 22 passenger seats. The audible warning shall be greater than 60 dB(A).

IWG CLIV Phase 2 addresses development of a UN Regulation for buses and coaches. The 13th through 17th sessions, held between virtual and in-person meetings from March to May 2026, focused on drafting the bus UN Regulation, refining text on scope, definitions, visual signals, and transitional provisions. Feedback from GRE and GRSG identified scope clarity issues and potential amendments to UN R48. Formal submission of a UN Regulation for buses is anticipated at the 80th GRSP session, with feedback requested before 10 June 2026, and subsequent drafting of a UN Regulation for light vehicles is planned to commence in the second half of 2026.

The 17th session of the Children Left in Vehicles informal working group met online on 28 May 2026 to finalise the draft UN Regulation for buses and coaches for presentation at the 79th GRSP session in June. The group agreed to retain the title and scope structure, remove Automated Driving System from definitions, retain Vehicle Master Control Switch wording, include Special Purpose Vehicles, remove the first sentence of paragraph 5.1, replace SOS Morse code signalling requirements with existing hazard warning lights combined with the horn, remove optional requirements from paragraph 5.4.4.6, remove Figure 2 and paragraphs 6.3.7 to 6.4.2, remove Section 11 Transitional Provisions, and remove Annex 2.