[Code of Federal Regulations] [Title 40, Volume 20] [Revised as of July 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR89.121] [Page 63] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 89_CONTROL OF EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES--Table of Contents Subpart B_Emission Standards and Certification Provisions Sec. 89.121 Certificate of conformity effective dates. The certificate of conformity is valid from the date of issuance by EPA until 31 December of the model year or calendar year for which it is issued. [59 FR 31335, June 17, 1994. Redesignated at 63 FR 56995, Oct. 23, 1998]