[Code of Federal Regulations] [Title 40, Volume 18] [Revised as of July 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR87.6] [Page 7] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 87--CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES--Table of Contents Subpart A--General Provisions Sec. 87.6 Aircraft safety. The provisions of this part will be revised if at any time the Secretary determines that an emission standard cannot be met within the specified time without creating a safety hazard.