The IWG is discussing the time interval from door lock to initial warning, with options of 15, 25, or 30 seconds as specified in para. 6.4.1. Investigation of door vibration effects during closing at three speeds (strong 3 m/s, medium 2 m/s, weak 1.2 m/s) on a medium SUV showed door vibration diminishes around 10 seconds. The system requires at least 3 times respiration cycles for accurate child detection judgment to reduce false-positive warnings in the field. A 25 seconds delay is recommended to allow appropriate time for accurate detection while accounting for vehicle vibration disturbance.

In-direct plus is a sensing system that, in addition to its indirect sensing functionality, has the ability to detect the presence of a live person inside the vehicle by means of sensing human attributes such as movement, temperature, sound, weight or any other sign of life. Direct sensing system detects the absolute presence of a human inside the vehicle by means of tracking heartbeat, respiration, movement, or any other sign of life. Indirect sensing system derives the potential presence of a subject or object inside the car based on logic using information such as door opening, pressure or capacitive sensing.

CLEPA supports the general approach in the current draft UN R for children left in vehicles regulation. Systems shall detect presence of children through a technology neutral approach based on performance requirements. Door-logic based systems have known weaknesses and are insufficient as standalone solutions. Systems shall appropriately address situations where children are unknowingly or knowingly left in vehicles, with suitable test cases covering real-life relevant situations and child restraint system installations. CLEPA proposes replacing references to in-direct plus or direct sensing systems with sensing system throughout the regulation.

Analysis examined 14 cases in Japan where child fatalities occurred after children were left unattended in passenger vehicles of category M₁ and N₁ between January 1984 and April 2025. Indirect sensing could potentially have generated an alert in 13 cases, while direct sensing could potentially have generated an alert in 5 cases. Based on these findings, retaining indirect sensing as an option for UNR is proposed.

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 21st IWG CLIV Session agenda for 8–11 September 2026 at UTAC Autodrome de Linas-Montlhry, France, focuses four meeting days on light vehicles. Drafting work with demonstrations occurs throughout the week. Day 1 includes introduction, official welcome, agenda adoption, progress summary, group photo, drafting regulatory text for LVs, research presentation on hot cars, and vehicle demonstration. Days 2–4 comprise drafting sessions for UNR for LVs, presentations including ISO WG on surrogate progression and vehicle demonstration, with closing remarks each day. The meeting ends 17:00 on Friday 11 September 2026.

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.

Regarding buses and coaches scope, delegates supported defining school buses as Special Purpose Vehicles, enabling inclusion without creating a harmonized international category. Comments are due by 14 August. The draft light vehicle UN Regulation was uploaded for review with comments due before or during the September in-person meeting in France. An in-person meeting is scheduled for September 2026.

The UN IWG for Children Left in Vehicles is in Phase 2 developing a new UN Regulation for vehicle categories M₂ and M₃. The draft UN Regulation includes requirements for visual and audible external warnings in buses and coaches to prevent children being left inside. The external warning shall be visual and audible, with the visual warning remaining on for at least 15 seconds then off for no greater than 30 seconds, repeating in cycles lasting no less than 10 minutes, using type approved direction indicator lamps all flashing with the same frequency. The audible warning shall remain on for at least 15 seconds then off for no greater than 30 seconds, repeating in cycles lasting no less than 10 minutes, and shall be greater than 60dB(A). Both warnings shall stop immediately after the physical inspection system is disarmed or the vehicle master control switch is turned on. The IWG intends to permit audible devices approved to UN Regulation No. 28 or UN Regulation No. 165 to generate the external audible warning.

The Children Left in Vehicles Informal Working Group holds its 19th session on 23 July 2026 from 17:00 to 19:00 Australian Eastern Standard Time online. The agenda includes feedback on drafting a UNR for light vehicles and consideration of a September face-to-face meeting in Paris.

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 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 engaged when the vehicle master control switch is turned off and disarmed via an inspection confirmation device located behind the rearmost passenger seat. An external visual and audible warning must be generated within 3 minutes for buses not exceeding 22 passenger seats, or within 5 minutes for buses exceeding 22 passenger seats, if the system is not disarmed. The visual warning shall remain on for at least 15 seconds, then remain off for no greater than 30 seconds, repeating in cycles lasting no less than 10 minutes. The audible warning shall be greater than 60 dB(A) with the same cycle requirements. Conformity of production procedures shall comply with Schedule 1 E/ECE/TRANS/505/Rev.3, with suitable controls checking dimensions and quality procedures.

UTAC is an automotive test and development center located in Linas-Montlhry, approximately 30 minutes from Paris Orly Airport. The organization operates multiple proving grounds globally, including facilities in Mortefontaine, Millbrook, Finland, and Oued Zem, with over 70 kilometers of test tracks across locations. UTAC provides event and training spaces, including a main modular venue called Le 1924 and a VIP Motul meeting room, alongside specialized testing capabilities for autonomous vehicles, connected vehicles, and electric vehicle development.

Proposal to establish uniform provisions concerning approval of M₁ and N₁ vehicles to assist in prevention of child occupants left inside, specify that vehicles of category M₁ with rear row designated seating positions that can accommodate a Child Restraint System and vehicles of category N₁ with more than one seating row, a Gross Vehicle Mass not exceeding 3,500 kg, and a rear row designated seating position that can accommodate a Child Restraint System shall be equipped with an in-direct plus or direct sensing system, require the system to detect Children Left in Vehicle events for all rear designated seating positions that can accommodate a Child Restraint System with default setting on, allow temporary or long-term deactivation under specified conditions with automatic reinstatement, require warnings to be given immediately after all doors are closed and locked with no more than fifteen to thirty seconds permissible delay and lasting at least ten seconds repeating every ninety seconds for total duration of no less than twenty minutes unless cancelled, establish test procedures including CLIV surrogates aged zero, three, and six years respectively, and specify conformity of production and modification procedures.

UTAC, Linas-Montlhry will host the CLIV IWG meeting 8–11 September 2026. The meeting room, Hellé Nice, is 4080 m², renovated in 2021, accessible without elevator, multimedia equipped, and near the main entrance. Accommodation options include Ibis Montlhry Paris Sud, B&B Hotel Brétigny-sur-Orge, and Comfort Hôtel Linas Montlhry; UTAC can arrange morning and afternoon transport. On-site catering includes water, coffee, tea, and paid lunch through the cafeteria at 15–20 per person. Wi-Fi and French Type E electrical outlets will be available. Delegates should confirm participant numbers by the first week of September using the attendance details form.

The 18th session of the Children Left in Vehicles Informal Working Group convened online on 25 June 2026. Feedback from GRSP on the draft UN Regulation for buses and coaches was positive, with a 10 July submission deadline for further comments. Australia will circulate a preliminary draft UN Regulation for light vehicles to Vice-Chairs before the September face-to-face meeting in Paris. The bus UN Regulation will initially include only Physical Inspection Systems, while light vehicle discussions will address indirect, indirect-plus, or direct sensing systems. A trilateral meeting between Australia, the United States, and Canada made constructive progress on Global Technical Regulation development, with potential for a November WP.29 vote.

UN IWG CLIV presented a draft UN R regulation proposal for buses at May UN GRSP session covering physical inspection system with no sensing required. Discussions on light vehicle regulation, paused since early 2026, can now resume. Light vehicles will have sensing related performance requirements. ISO CPD surrogates availability will be crucial to implement the regulation. UN IWG CLIV will hold a 4-day workshop from 08–11 September, likely at UTAC/France, focusing on light vehicles, welcoming ISO CPD expert participation and presentations on ISO CPD status and test tools.

The agenda includes feedback from the June GRSP session on the submitted draft UN Regulation, next progression of work for light vehicle drafting and consideration of a September face-to-face meeting.

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.