Simulation of UN R17 whiplash protection component tests and rear impact sled tests using finite element models of a Toyota Auris seat showed the UN R17 test protocol is not robust. A modified seat model approved in component tests (displacement, strength, energy dissipation) but failed the dynamic performance test. Component tests allow large variation in seat properties and do not ensure approval of the dynamic performance test. Seat properties with large effects on whiplash protection in dynamic performance tests can vary substantially with minimal effects in component tests.

Whiplash injury causes neck pain, stiffness, headache, shoulder pain, and neurological symptoms, with women more sensitive than men. Symptoms occur consistently across rear, frontal, and lateral impacts. Research focuses on nerve injury in spinal ganglia as the injury site, as this explains why long term whiplash symptoms include neurological symptoms independent of crash direction. The Neck Injury Criterion (NIC) measures injury using the formula NIC = 0.2Δa + Δv², where Δa is acceleration difference and Δv is velocity difference. Whiplash motion causes rapid volume changes inside the vertebral canal, with epidural blood volume pumped to compensate. Animal experiments using pressure sensors show pressure changes in skull and spine at different vertebral levels during whiplash events.

Field data shows reduction in risk for both males and females, though risk difference between males and females remains with higher risk for females regarding soft tissue neck injuries. Purely geometry-based assessment may not be sufficient; minimizing relative spine movements, forward rebound, evenness and energy absorption are important for equitable protection against whiplash. Discussion concluded that headrests often remain in highest position and do not protect occupants of lower stature optimally, which should not be considered misuse. A forgiving design of backrest and headrest should be targeted. Important to avoid suboptimization and assess more than one single point.

The UN IWG on Cyber Security and OTA held its 38th session 29 June–1 July 2026 in London with remote participation. The group adopted the provisional agenda and minutes from the 37th session. Three items from the IWG were presented at the May GRVA meeting: multistage vehicle documents to become working documents for September; RXWIN documents with elements in square brackets to be resolved; and SUMs document returned for further discussion. For R155, the group agreed to forward multistage amendment proposals as working documents to September GRVA. The UK proposal on STU and component approval for R155 was discussed extensively; the UK will draft a proposal for components only. The UK proposal on remote operation for ADS requires further development. The group will review ADS GTR cyber and software provisions. RXWIN proposal documents were adapted; R155 was removed and R89 and R156 sections amended; reviewers may address concerns by 31 July 2026. Germany’s proposal requiring the same Type-Approval Authority for CSMS and vehicle type approval was discussed; a dedicated meeting will be scheduled. The UK proposal on approvals for out-of-scope vehicle types was introduced. Draft Terms of Reference were revised and will be forwarded to GRVA for September approval. The next meeting is scheduled for 3 September 2026, 12:00–15:00 CET.

Proposal to insert a new paragraph 0 introducing supplements 4 and 5 to the 04 series of amendments extending the Regulation to vehicles of categories X and Y, amend paragraph 1 to establish scope and exemptions for categories X and Y, amend paragraphs 2.8, 2.22, 2.29, 2.32, 2.44, and 2.45 to define test procedures and reference areas for vehicles without drivers or manual controls, and amend paragraph 5.3.1.2 to clarify automatic return of ARHSS when vehicle speed exceeds 25 km/h or while an ADS feature is active.

Proposal to establish uniform provisions concerning approval of vehicles of category N₁Y regarding fuel system integrity protection, electrical shock protection, and vehicle crash compatibility in frontal, rear-end, and lateral collisions, modify frontal impact test procedures to reference either UN R94 or UN R137 at manufacturer choice in agreement with the Technical Service, add Crash Compatibility Criterion and Crash Compatibility Value definitions and requirements not exceeding 40 g and 100 g × tonne respectively, modify lateral impact test provisions to reference UN R95 without specific side pole impact applicability, modify rear-end impact test procedures to reference UN R153, add post-crash hydrogen fuel system integrity assessment procedures, add provisions allowing vehicles derived from compliant category X vehicles to be deemed compliant, add electrolyte leakage and REESS retention requirements for electric powertrains, permit vehicles with maximum design speed not exceeding impact speed to be tested at their maximum design speed with compliance to post-impact requirements, and establish extension procedures for vehicles derived from previously approved types.

PMP webex meeting scheduled for 9th July 2026, 12:00–14:30 CET. Agenda includes an overview of amendments to Brakes GTR 24 and UN R179, task force discussions on layout and testing topics, vehicles limited speed, brake replacement parts, electromechanical brakes GTR and UNR, HD brakes, projects on tyres and brakes, and any other business. Webex meeting access details and link provided.