26. The Secretary of the informal group on HDH introduced GRPE-64-07, GRPE-64-13 and GRPE-64-14. He illustrated the results of the ninth and tenth HDH informal group meetings and summarized the results of the research programme on an emissions and CO2 test procedure for HDH (now finalized). Underlining that more work is needed before a worldwide test procedure can be drafted, he stated that the discussion on chassis dynamometer and power-pack testing is expected to continue on the basis of inputs from ongoing programs by the Contracting Parties (with the delivery of inputs expected by the end of 2012), that the validation step 1 based on SILS (Software-in-the-loop simulation) is expected to start in June 2012, and that the validation step 2 with real heavy duty vehicles should start around March 2013.

27. Illustrating an updated roadmap, the HDH Secretary announced a delay of a few months with respect to the original plan. Following some considerations on financial issues related to validation step 1, he outlined the agenda of the next meetings of the HDH group.

28. GRPE acknowledged the work progress of the HDH informal group, endorsed validation 1 and the revised roadmap, and agreed that a formal request to WP.29 to extend the mandate of the HDH group is not necessary for the time being. GRPE agreed that the group should meet in conjunction with its session in January 2013.