Status report on the Special Interest Group on Component & Separate Technical Unit work on UN R158 and UN R159. The SIG-C&STU is developing proposals to add Component and Separate Technical Unit approval routes to UN R151, UN R158, UN R159, and UN R166. For UN R159, Supplement 4 is under review with documents at GRSG-132. For UN R158, a Proposal for Supplement 7 is in development. The group requests feedback on structural approaches and timelines for working document submissions by January 2027.

Presentation on truck underrun accident prevention examining active safety system performance and rear underrun protection crashworthiness. ADAS testing of seven modern vehicles (2025–2026) at speeds 56–130 km/h toward stationary truck targets in four scenarios found systems currently unable to reliably prevent collisions on motorways. Conspicuity testing of trailers identified reduced performance with offset approaches and darkness. Crash testing of European UN R58.03 rear underrun protection against US IIHS Toughguard at 56 km/h demonstrated latest European RUP incapable of preventing underrun, with recommendation that regulation mandate tougher RUP standards.

Proposal to amend the table in para. 5.1. to add rows for battery master switch de-energizing electrical systems, thermal shield for endurance braking system, electric power train, vehicle endurance braking, hydrogen fuel cell, and tyre pressure monitoring system; amend para. 5.1.1.8. to 5.1.1.8.2. to modify de-energizing electrical circuits systems requirements and add control device requirements for vehicles equipped with camera monitoring systems according to UN R461; amend para. 5.1.3.5.1. to modify general provisions for electric power train systems; amend para. 5.1.3.6. to modify thermal shield requirements for vehicle endurance braking systems; renumber para. 5.1.3.7. to 5.1.3.6.; amend para. 5.1.3.7.3. to modify shut-off devices requirements for hydrogen containers; insert new para. 5.1.7. to require tyre pressure monitoring systems according to UN R1412; restructure para. 10. transitional provisions to align with WP.29 guidelines and ADR-2027 implementation dates; and amend Annex 2 approval mark models.

Report on a workshop organized by the Kingdom of the Netherlands on 25 August 2026 in Brussels to address transparency provisions in UN R43. The workshop discussed current transparency requirements, alternative test procedures for reflection, definitions such as chameleon effect, and amendments to working document ECE/TRANS/WP.29/GRSG/2026/20. Participants agreed transparency provisions are not direction-dependent, confirmed the importance of driver visibility, and noted the absence of measurement procedures or objective criteria for reflection levels. The proposal is to add a footnote to clarify requirements for the driver’s forward field of vision, with future evaluation of whether more objective measurement provisions on reflections are needed.