[Code of Federal Regulations] [Title 40, Volume 9] [Revised as of July 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR63.61] [Page 92] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 63_NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES--Table of Contents Subpart C_List of Hazardous Air Pollutants, Petitions Process, Lesser Quantity Designations, Source Category List Sec. 63.61 Deletion of methyl ethyl ketone from the list of hazardous air pollutants. The substance methyl ethyl ketone (MEK, 2-Butanone) (CAS Number 78- 93-3) is deleted from the list of hazardous air pollutants established by 42 U.S.C. 7412(b)(1). [70 FR 75059, Dec. 19, 2005]