6. The expert from the United Kingdom, on behalf of the Chair of the Informal Working Group (IWG) on the UN Global Technical Regulation (UN GTR) No. 7 – Phase 2, clarified that the IWG was following a more empirical approach to determine biomechanical criteria and that alternative methodologies were under study. He reported that the IWG expected to finalize proposals for the December 2016 session of GRSP on UN GTR No. 7 and on Addendum 1 to Mutual Resolution No. 1 (M.R.1) to incorporate Bio Rear Impact Dummy (BioRID) specifications. He concluded that an extension of the mandate of the IWG until March 2017 was needed to complete the final proposals and that AC.3 endorsed this request at its March 2016 session.