[8F/1, 4A/437, 7B/73, 7C/190, 7D/112, 8B/113, 8D/325, 10-11S/254] Liaison statement from Task Group 1/5 to Working Parties 4A, 8B, 7C, 7D, 8B, 8D, 8F and JWP 10-11S (Chairman) concerning a PDNR on the protection of passive services from unwanted emissions