Proposal to require the electric side windows of the front seat row to function for at least ² minutes from the time of a vehicle entering water.

Proposal to establish a submergence test procedure requiring that at least one window per row of seats be capable of being fully opened after a vehicle enters water for occupant escape, with the window operable up to 2 minutes after submergence as designed by the manufacturer, defining container dimensions to accommodate the vehicle without wall or floor contact during the 2-minute period except when fully submerged, permitting open-water test sites provided they comply with test conditions while prohibiting freshwater lakes, reservoirs, and saltwater bodies, requiring the master control switch position allow window operation, specifying unladen kerb mass with measuring apparatus not changing axle reference load by more than 5 per cent, lowering the vehicle into water-filled container at horizontal angle 0–10 degrees with time zero defined as when lowering straps become slack and vehicle floats freely, requiring the vehicle remain in water for 2 minutes from time zero without floor contact until fully submerged, requiring window operation by remote system after 2 minutes with vehicle immersed, and permitting alternative subsystem tests demonstrating window opening functionality under submerged conditions.

Revised proposal based on document GRSP/2024/7 to update references to the three-dimensional “H” point measurement and calibration procedure pursuant to moving such provisions from the Consolidated Resolution on the Construction of Vehicles (R.E.3) to Mutual Resolution No. 1.

Changes to NCAP testing oblige the use of load limiters on safety-belts with lower threshold values that yield less thorax compression but also allow for greater forward displacement of the occupants. To address the greater forward displacement of rear occupants, UN R17 is under revision to require more stringent energy dissipation performance for those areas of the rear of seats (including the head restraints and parts mounted on the seat) where the head of the rear occupant may come into contact. UN R21 allows for alternative testing of the rear parts of seats (paras. 5.7-5.7.3. ) However, in light of the changes to UN R17, this alternative approach is no longer valid. This proposal would delete the alternate method and expands the scope of UN R21 to include testing of any parts mounted on the seats.

Proposal to update references to the three-dimensional “H” point measurement and calibration procedure pursuant to the transposition of these provisions from the Consolidated Resolution on the Construction of Vehicles (RE3) to Mutual Resolution No. 1.