[Code of Federal Regulations] [Title 40, Volume 30] [Revised as of July 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR1065.301] [Page 663] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 1065_TEST PROCEDURES AND EQUIPMENT--Table of Contents Subpart D_Analyzer and Equipment Calibrations Sec. 1065.301 Overview. Calibrate all analyzers and equipment at least annually, but make the actual frequency consistent with good engineering judgment. We may establish other guidelines as appropriate. Calibrate following specifications in one of three sources: (a) Recommendations from the manufacturer of the analyzers or equipment. (b) 40 CFR part 86, subpart F or subpart N. (c) 40 CFR part 90, subparts D and E, as applicable.