UN IWG CLIV workshop briefing on ISO/WD 26315 status. The working draft specifies child presence detection surrogates with geometric, optical, near-infrared, radar-related and physiological properties representing newborn to 6-year-old children. Core clauses and three normative annexes address surrogate classes, dimensional tables, visual and near-infrared recognition properties, and radar-specific recognition properties. Open technical decisions include radar bands by region, respiration data by surrogate class, motion requirements as mandatory versus optional, optical and near-infrared clothing details, validation methods and measurement procedures, and dimensional alignment with Euro NCAP standards.

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.

Proposal to establish requirements for in-direct plus or direct sensing systems to detect children left unattended in M1 and N1 vehicles under 3,500 kg. Systems shall detect Child Occupants Left Inside (CLIV) events for rear seating positions accommodating child restraint systems and issue audible or audible and visual warnings at least 60 dB(A) within 15–30 seconds of locking all doors, lasting at least 10 seconds and repeating every 90 seconds for at least 20 minutes unless cancelled. The default system setting shall be ON, with deactivation available temporarily for single journeys or long-term for maximum 30 days. Testing shall use CLIV surrogates aged 0, 3, and 6 years per ISO 26315, covering multiple test scenarios including warning delay, cancellation, and temporary deactivation.

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.

From 1998 to 2025, 1,041 pediatric vehicular heatstroke fatalities occurred, with an average of 37 fatalities yearly. NHTSA assessed direct sensing radar systems in Genesis GV70, Toyota Sienna, and other vehicles, finding detection rates varied between vehicles and seating locations. Testing used Child Presence Detection dummies simulating newborn infants. NHTSA also evaluated aftermarket systems including retrofit devices like Ride & Remind and non-retrofit devices like SensorSafe, finding widely varying detection and alerting features. NHTSA continues investigating performance of strategies to reduce pediatric vehicular heatstroke risk and developing test procedures and performance criteria for evolving technologies.

Pediatric vehicular heatstroke occurs when body temperature exceeds 104°F, with children’s body temperatures rising three to five times faster than adults’. An average of 37 pediatric vehicular heatstroke fatalities occur yearly from 1998–2024, primarily from children being forgotten in vehicles. NHTSA has tested retrofit, aftermarket, and vehicle manufacturer unattended child reminder systems using direct and indirect sensing approaches. Testing revealed Bluetooth-connected devices alert at varying distances depending on signal strength, capacitive and pressure devices face false trigger risks, and direct sensing radar systems show inconsistent detection across vehicles and seating positions. NHTSA plans to publish an Advanced Notice of Proposed Rulemaking seeking comments on amending Federal Motor Vehicle Safety Standards to require rear seat occupant detection systems.

As of 2025, Euro NCAP only rewards direct sensing systems. Of 113 vehicles rated under the 2025 protocol, 69 were battery electric vehicles. Direct sensing systems increased from 12% in 2024 to 31% in 2025, while indirect systems decreased from 46% to 27%. Overall, 36% of tested vehicles in popular categories were equipped with direct sensing, except superminis. All direct sensing systems cover rear seats; 40% also cover front passenger seats. Of vehicles tested, 60% provide intervention alongside initial and escalation warnings. All vehicles with direct sensing systems are equipped with a battery for propulsion. (PowerPoint version of CLIV-21-07)

As of 2025, Euro NCAP only rewards direct sensing systems. Of 113 vehicles rated under the 2025 protocol, 69 were battery electric vehicles. Direct sensing systems increased from 12% in 2024 to 31% in 2025, while indirect systems decreased from 46% to 27%. Overall, 36% of tested vehicles in popular categories were equipped with direct sensing, except superminis. All direct sensing systems cover rear seats; 40% also cover front passenger seats. Of vehicles tested, 60% provide intervention alongside initial and escalation warnings. All vehicles with direct sensing systems are equipped with a battery for propulsion. (PDF version of CLIV-21-08)

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 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.

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.

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.

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.

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.