Williams Brothers Engineering Company — Pipeline Safety Interpretation

Page 1Mr. 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. Sincerely, /signed/ Melvin A. Judah Acting Associate Director for Pipeline Safety Regulation Materials Transportation Bureau Enclosures NOTE: ATTACHED ARTICLE No. 82-7 DB C:\WP51\INTERPRE\192\5\73-09-05 1#

Page 2Date: July 30, 1982 DEPARTMENT OF TRANSPORTATION RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION MATERIALS TRANSPORTATION BUREAU _____________________________________________________________________________ PIPELINE SAFETY REGULATORY INTERPRETATION _____________________________________________________________________________ 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 DB C:\WP51\INTERPRE\192\5\73-09-05 2#

Page 3Pipeline Safety Regulation Materials Transportation Bureau DB C:\WP51\INTERPRE\192\5\73-09-05 3#

Page 4November 6, 1980 Mr. Melvin A. Judah Acting Associate Director of Pipeline Safety Regulation Materials Transportation Bureau Department of Transportation Washington, D. C. 20590 Dear Sir: This is in regard to requirements of Section 192.5 of the Code of Federal Regulations, Title 49, Part 192, Subpart A. My specific question regards the intent of Paragraph (f) when applying the provisions for adjustments to requirements of the preceding paragraphs as permitted by Subparagraphs (2) and (3). The attached sheet contains two examples, which represent ny understanding of the application of adjustments permitted by Paragraph (f), Subparagraphs (2) and (3). This understanding is based on the premise that when the Class Location requirement for a cluster of buildings is satisfied, these dwellings are then not included in the count of dwellings for the continuous 1-mile class location criteria in the circumstances described by these examples. Stated in a different manner, it is assumed that the intent of Paragraph (f) is to offer relief from class location requirements of the preceding paragraphs employing the continuous 1-mile criteria; which, in the case of the two examples, would require extending the length of the higher class location unit due to the influence of the cluster of dwellings. In the examples, the pipeline is onshore, the buildings are all single dwellings intended for human occupancy, and Paragraphs 192.5(e), 192.5(d)(2)(i) and 192.5(d)(2)(ii) do not apply. While reviewing Section 192.5 it was noted that Paragraph (e) refers buildings with four or more stories in a plural sense, while Paragraph (f) Subparagraph (1) refers building in a singular sense. This raised the question whether encroachment by a single building of four or more stories would require up-grading to a Class 4 location. This is a separate general question and not related to the specific questions pertaining to the examples. DB C:\WP51\INTERPRE\192\5\73-09-05 4#

Page 5Any comments or guidelines you can give relative to these specific questions and the general intent of Paragraph (f) would be appreciated. Very truly yours, Williams Brothers Engineering Company John Suglove, Project/Manager NOTE: DIAGRAM ATTACHED DB C:\WP51\INTERPRE\192\5\73-09-05 5#