The system and procedures for sampling and measurement of smoke emissions shall be as specified in Appendix 2 to ICAO Annex 16, Volume II, Environmental Protection, Aircraft Engine Emissions, Second Edition, July 1993, effective July 26, 1993. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This document can be obtained from, and copies may be reviewed at, the respective addresses listed in §34.64.