20. The Chair of the informal group on MACTP reported on the work progress made in the EU framework (GRPE-65-32). He reported that the MAC efficiency test phases are completed. The procedure was found to be robust, but some items are still open and need discussion or further investigation. The reproducibility (intra-lab variation), in particular, is not satisfactory and is likely to require an increase in the number of tests and the statistical evaluation of their results. Looking at regional developments, he explained that Japan is focusing on the development of a MAC test procedure based on whole vehicle driving over a dynamic cycle. The test phase, currently ongoing, should be concluded at the end of March 2014. This is going to be followed by the definition of the dynamic test procedure. In Europe, the MAC procedure is seen as a part of the integrated approach and it could lead to separate label for MAC systems mounted on vehicles or consumer information instrument integrated in the existing vehicle CO2 emission label. The MACTP Chair mentioned that one of the possible developments foresees the transposition of the MAC test procedure as a voluntary (i.e. optionally applicable) test procedure in either UN Regulation Nos. 101 or 83.

21. GRPE acknowledged the work progress and agreed that the group should meet again once the European test procedure is completed and can be reviewed, or when new information needs to be shared.