26. The expert from CLEPA introduced ECE/TRANS/WP.29/GRSP/2015/18, aimed at clarifying the provisions for dynamic testing of the rear seat restraint systems. She explained that the proposal aimed at updating requirements that were originally designed for seating positions that did not yet require three-point safety-belts; she added that the situation had developed with the introduction of load limiters that allowed for further displacement of occupants. Comments from GRSP experts on the proposal were incorporated into GRSP-58-35 during discussion. The expert from the Netherlands introduced ECE/TRANS/WP.29/GRSP/2015/27 that was also linked to ECE/TRANS/WP.29/GRSP/2015/18 because the of displacement of occupants due to safety belt load limiters that were installed on seats other than front seats. He explained that the proposal needed corresponding amendments to UN Regulations Nos. 21, 25 and 80. The expert from OICA argued that the proposal should address just those seating positions that needed energy absorption requirements. The expert from CLEPA also underlined the need to focus the energy dissipation tests on the parts of back seats where actual impacts occur.

27. Finally, GRSP agreed to establish a group of interested experts, led by the expert from the Netherlands, on new restraint system technology to develop provisions on this matter for all the relevant UN Regulations. GRSP agreed to resume discussion on this subject at its May 2016 session and to refer ECE/TRANS/WP.29/GRSP/2015/18, ECE/TRANS/WP.29/GRSP/2015/27 and GRSP-58-35 to the group of interested experts.

13. The expert from CLEPA introduced a presentation (GRSP-57-25) to explain ECE/TRANS/WP.29/GRSP/2015/16 and GRSP-57-03 (superseding ECE/TRANS/WP.29/GRSP/2015/4) aimed at clarifying the provisions for dynamic testing of rear seat system and advanced restraint system approval. The expert from Japan argued that the proposal was not assessing the air-bag performance through UN Regulation No. 94 because it was addressing other occupants than those seating in lateral frontal positions. The expert from France clarified that the proposal was addressing the concept of restraint systems to other seating positions than front outboard positions. The expert from EC suggested aligning the proposed provisions with those of UN Regulation No. 21, concerning the speed of impact of seating position protected by an air-bag. Accordingly, the expert from CLEPA introduced GRSP-57-28 incorporating the comments received during the discussion. The experts from France and Japan raised study reservations on the proposal. Moreover, the expert from the Netherlands noted that the proposal would affect not only the safety-belt component but also the vehicle. The experts from EC and OICA stated that the proposal should be discussed as a full package with the corresponding amendment to UN Regulation No. 17, namely ECE/TRANS/WP.29/GRSP/2015/14 (see para. 19 below). GRSP agreed to resume discussion on this subject at its December 2015 session and requested the secretariat to distribute GRSP-57-28 with an official symbol.

19. Referring to the discussion held under agenda item 7 (see para. 13 above), the expert from the Netherlands introduced ECE/TRANS/WP.29/GRSP/2015/14, calling for increased energy absorption capabilities on the rear part of seat backs, taking into account the increased forward displacement of the rear occupants restrained by new safety-belts equipped with improved load limiter devices. However, he proposed to defer the discussion at the December 2015 session of GRSP, since the proposal would involve a parallel amendment to UN Regulation No. 16 to extend contact requirements of occupants against rear seats backs. GRSP agreed to resume discussion at its next session on the basis of a new proposal as an outcome of an exchange of views among the experts from the Netherlands, CLEPA, OICA and other interested parties.