49 C.F.R. § 192.706 Transmission lines: Leakage surveys.
Title 49 - Transportation
Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line which transports gas in conformity with §192.625 without an odor or odorant, leakage surveys using leak detector equipment must be conducted— (a) In Class 3 locations, at intervals not exceeding 7 (b) In Class 4 locations, at intervals not exceeding 4 [Amdt. 192–21, 40 FR 20283, May 9, 1975, as amended by Amdt. 192–43, 47 FR 46851, Oct. 21, 1982; Amdt. 192–71, 59 FR 6585, Feb. 11, 1994]
Title 49: Transportation
PART 192—TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS
Subpart M—Maintenance
§ 192.706 Transmission lines: Leakage surveys.