Valve Maintenance: Transmission and Distribution Lines (17.11)

Valve Maintenance: Transmission and Distribution Lines (17.11)

Criticality: Medium
Progress: Addressed, Not Adequately
Score: 12
DOT Relevance: 192.745 192.747

Description of Key Area

Sections 192.745 to 192.747 of Subpart M (Maintenance) of 49 CFR 192 address valve maintenance for transmission and distribution lines. The Code states the frequency at which these valves must be inspected.

Section 192.745 (Valve Maintenance: Transmission Lines) states, Each transmission line valve that might be required during any emergency must be inspected and partially operated at intervals not exceeding 15-months, but at least once each calendar year.

Section 192.747 (Valve Maintenance: Distribution Systems) states, Each valve, the use of which may be necessary for the safe operation of a distribution system, must be checked and serviced at intervals not exceeding 15 months, but at least once each calendar year.

Discussion of Criticality

For hydrogen pipeline purposes, regulations as to the frequency of inspection valves for transmission and distribution lines must be determined.

Discussion of Progress

This topic will be addressed in ASME B31.12.


Standards must be established relating to valve maintenance on hydrogen transmission lines and hydrogen distribution systems. These standards must be incorporated by reference into the federal code.