Criticality: High Progress: Not Addressed Score: 40 DOT Relevance: §192.609 – §192.611
Description of Key Area
The subject of change in
class location falls under the Subpart L (Operations) of 49 CFR 192. Class
location refers to the distance a structure must be located from the pipeline.
A “class location unit” is defined in 49 CFR 192 as “an on-shore area that
extends 220 yards on either side of the centerline of any continuous 1-mile
length of pipeline.”
Discussion of Criticality
The parameters for class
location are based on natural gas considerations. The underlying definition of
class location should be reviewed for hydrogen.
Discussion of Progress
ASME B31.12 plans on
following the ASME B31.8 code with input from the modified section 3.2 of ASME
B31.8S.
Recommendations
Standards should be
established for change in class location of hydrogen pipelines and incorporated
by reference into the federal code including what the maximum allowable
operating pressure of the hydrogen pipe should be and at what population
density is a change in class location warranted. The class location unit needs
to be revisited to confirm whether it is appropriate for hydrogen. The change
in class location criteria in 49 CFR 192 also should be revisited.
