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Interpretation Response #PI-82-014 ([Williams Brothers Engineering Company] [John Suglove])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Williams Brothers Engineering Company

Individual Name: John Suglove

Location State: TX Country: US

View the Interpretation Document

Response text:

Mr. John Suglove

Williams Brothers Engineering Company

Suite 300 W

50 Briar Hollow Lane

Houston, TX 77027

Dear Mr. Suglove:

I apologize for length delay in answering your letter concerning applications of the class location definitions contained in 49 CFR §192.5.

Your application of paragraph (f) of §192.5, to restrict the boundaries of Class 2 and Class 3 locations created by a cluster of buildings in otherwise Class 1 situations such as you portray in your drawing is not correct. Because the two clusters portrayed are within a continuous 1-mile length of pipeline, they affect one another and in the example you give would cause the class location to be Class 3 to a point of 220 yards beyond the extremities of the two "combined" clusters. The enclosed highlighted excerpts from Notice 70-4 proposing the regulation and the preamble to the original 49 CFR part 192 (FB 35, 13251) should clarify the meaning of the regulation regarding clusters of buildings.

An interpretation of §192.5(e) and (f) regarding encroachment of a single 4-story building is enclosed.



Melvin A. Judah

Acting Associate Director

for Pipeline Safety Regulation

Materials Transportation Bureau








NOTE: A pipeline safety regulatory interpretation applies a particular rule to a particular set of facts and circumstances, and, as such, may be relied upon only by those persons to whom the interpretation is specifically addressed.

SECTION: 192.5(e) and (f)

SUBJECT: Class locations.

FACTS: Paragraph (e) refers to buildings with four or more stories in a plural sense. Paragraph (f)(1) refers to building in a singular sense.

QUESTION: Does encroachment by a single building of four or more stories require upgrading to a Class 4 location?

INTERPRETATION: Having a single four or more story building within 220 yards of a gas pipeline does not require upgrading to Class 4 requirements because paragraph (e) states in part: "where buildings with four or more stories above ground are prevalent." The use of "prevalent" indicates that they are common or that there are more than one such building in the area. Therefore, a single four or more story building would not cause an area to be designated a Class 4 location.

Subparagraph (f)(1) uses "building" in the singular because it is referring to the nearest building in group or cluster to which the boundary adjustment of 220 yards applies in relation to other dwelling units.

Melvin A. Judah

Acting Associate Director

Pipeline Safety Regulation

Materials Transportation Bureau

Regulation Sections

Section Subject
192.5 Class locations