What does 49 CFR 192.706 require for transmission line leakage surveys?

According to 49 CFR 192.706, "Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year." However, for transmission lines that transport gas without an odor or odorant, more frequent surveys are required: in Class 3 locations, at intervals not exceeding 7 1/2 months, but at least twice each calendar year; and in Class 4 locations, at intervals not exceeding 4 1/2 months, but at least four times each calendar year.

This is compliance information, not legal advice — verify against the official eCFR and the issuing agency.