37. The expert from France, Chair of the FI IWG, introduced the status report of the group (GRSP-55-43) as well as the latest amendments (GRSP-55-20-Rev.1) to the official proposal (ECE/TRANS/WP.29/GRSP/2014/10) of a new UN Regulation on frontal impact with focus on the restraint system. He added that the IWG focused on two possible scenarios for the threshold of front passenger’s thorax compression criteria:
(a) thorax compression criteria (Thcc) of ≤ 34 mm (considering the injury risk curve for the elderly 5th percentile female);
(b) Thcc ≤ 42 mm (considering the injury risk curve for the 5th percentile female).

38. He asked GRSP for guidance on choosing the scenario to be addressed by the draft UN Regulation. The expert from EC suggested that the first scenario complemented by an additional test (e.g. sled test) with a 95th percentile male dummy. However, the expert from France reminded GRSP that the proposal aimed to reduce the number of tests. The expert from OICA presented a recommendation (GRSP-55-42) for a Thcc ≤ 42 mm to address the 5th percentile female because a Thcc of ≤ 34 mm would only address a limited percentage of the population and because the test tool variations need to be taken into account. He remarked that the higher injury risk for elderly occupants would be considered by a reduced Thcc threshold of 42 mm for the 50th percentile male dummy Hybrid III as was also proposed for UN Regulation No. 94. GRSP finally agreed to resume consideration of this agenda item at its December 2014 session and requested its experts to provide clear guidance on the two above-mentioned scenarios. The secretariat was requested to distribute GRSP-55-20-Rev.1 with an official symbol at the next session of GRSP.