The CLIV IWG 20th session reviewed its draft proposal for a bus and coach UN Regulation submitted to GRSP in December 2026, retaining operational isolation terminology with editorial corrections, defining scope as M2 and M3 class B and III vehicles designed for carrying children, and adopting a journey definition covering engine or motor operation until 15 minutes after the vehicle master control switch is turned off. The IWG adopted a 1.5 ± 0.5 Hz repetition rate for warning signals and deferred light-vehicle UN Regulation drafting to a September face-to-face meeting in Paris.

Work-in-progress draft regulation to address the safety of children left in light vehicles, with changes to amend definitions of ‘Child’ or ‘Children’ to refer to individuals generally considered to be between 0 and 6 years old, replace “frequency” with “repetition rate” in warning requirements, and clarify system deactivation, warning delay, and internal visible warning procedures. The proposed regulation would cover vehicles of categories M₁ and N₁ with mass not exceeding 3,500 kg equipped with indirect sensing or direct sensing systems to detect children left unattended in vehicles.

The agenda includes finalization of the proposal for a UNR on buses and coaches, feedback on the drafting of a UNR for light vehicles, and discussion of a September face-to-face meeting agenda.