Pipeline Safety Interpretation PI-84-0100

Page 1PI-84-0100 January 10, 1984 Mr. James D. Shelby Attorney at Law 1148 Standard Building 1370 Ontario Street Cleveland, OH 44113 Dear Mr. Shelby: Your letter of December 22, 1983, requesting available interpretation involved eight questions concerning service lines supplying natural gas to a consumer, odorization of natural gas, and responsibilities of a pipeline operator for leak detection surveys. Your first four questions asked whether certain requirements of §§192.143, 192.159, 192.161(e), and 192.273 apply to service lines and for which you requested interpretations that are available. However, please note that in §192.3, the following definitions are given: "'Pipeline’ means all parts of those physical facilities through which gas flows in transportation, including . . ." and "'Service line' means a distribution line that transports gas from a common source of supply to (a) a customer meter or …” The key word here is transportation. Therefore, since a service line transports gas to a consumer, it is a pipeline and subject to the same requirements that would be generally applicable to pipelines. There are no interpretations on file which are relevant concerning these specific questions. Your fifth question asks "What are the minimum requirements of Sec. 192.361(d) as concern the use of Type L 1/2" I.D., 5/8" O.D. copper tubing which is connected to an outdoor meter riser assembly by means of a Style #90-65 Dresser reducing coupling and steel ells?" Section 192.361(d), Protection against pipe strain and external loading, is in performance language and applicable to all service lines. This is intended to tell what must be done and does not specify how this must be accomplished or relate to specific components. In response to your sixth question concerning odorization of gas, please note that §192.625(a) refers to "A combustible gas in a distribution line . . ." Filtration of odorant from natural gas by soil is not relevant to that specific requirement. In 1974, this office had a study (DOT/OPSO-75-08) conducted by the Institute of Gas Technology (IGT) titled "Study of the Properties of the Numerous Odorants and Assessment of Their Effectiveness in Various Environmental Conditions to Alert People to the Presence of Natural Gas." This study is available from the U.S. Department of Commerce, National Technical information Service (NTIS), Springfield, Virginia 22161, telephone (703) 487-4650. The study is identified in the NTIS system as PB 249528/AS. For your information, we are enclosing three pages copied from the IGT study that address odor retention in utility piping systems and odor retention under special conditions, including gas passage through soil. Your seventh question asks “Considering Sec. 192.721 and .723, under the following circumstances, what duty does an operator of a distribution system have to provide more than its usual annual or twice annually leak detection survey outside of a customer's residence: . . ." It should be noted that §192.723(b) requires a gas detector survey to be conducted on distribution systems in business districts at intervals not exceeding 1 year and outside of business districts at intervals not exceeding 5 years. There are no specific requirements for more frequent gas detector surveys in distribution systems that would be relevant to the circumstances you described. Your last question asks “. . . does the operator have a duty to warn the occupant-customer that digging near the service line might cause a leak that won't be detectable by smell?” There are no specific requirements relevant to the circumstances you describe; however, §192.615(d) states that "Each operator shall establish a continuing educational program to enable customers, the public, appropriate government organizations, and persons engaged in excavation related activities to recognize a gas pipeline emergency for the purpose of reporting it to the operator or appropriate public officials. The program and the media used must be as comprehensive as necessary to reach all areas in which the operator transports gas. The program must be conducted in English and in other languages commonly understood by a significant number and concentration of the non-English speaking population of the operator's area.” We hope that we have adequately responded to your questions and that you will find this information useful. Sincerely Original signed by Richard L. Beam Associate Director for Pipeline Safety Regulation Materials Transportation Bureau#

Page 2James D. Shelby Attorney at Law 1148 stnadard Buiding 1370 Ontario Street Cleveland, Ohio 44113 December 22, 1983 Mr. Richard L. Beam Associate Director for Pipeline Safety Regulation Materials Transportation Bureau U. S. Dept. of Transportation 400 Seventh Street, S.W. Washington, D. C. 20590 Re: 49 CFR Sec. 192.01, et seq. Dear Mr. Beam: Thank you for your letter of December 19, 1983 regarding the availability of interpretations of Part 192. I am hereby requesting the interpretations that are available regarding the following specific questions. 1. Do the general requirements of Sec. 192.143 apply to service lines? 2. Do the flexibility requirements of Sec. 192.159 apply to service lines? 3. Do the supports and anchors requirements of Sec. 192.161(e) apply to service lines? 4. Do the general requirements of Sec. 192.273 apply to service lines? 5. What are the minimum requirements of Sec. 192.361(d) as concern the use of Type L 1/2" I.D., 5/8" O.D. copper tubing which is connected to an outdoor meter riser assembly by means of a Style #90-65 Dresser reducing coupling and steel ells? 6. As applies to Sec. 192.625(a), what consideration is given to the fact that the odorant contained in natural gas will be adsorbed when the natural gas passes through soil? Are operators required to introduce odorants into their distribution lines which will remain readily detectable by a person with a normal sense of smell even after the natural gas has passed through soil, from a break in the service line, and entered the customer's basement? 7. Considering Sec. 192.721 and .723, under the following circumstances, what duty does an operator of a distribution system have to provide more than its usual annual or twice annually leak detection survey outside of a customer's residence: a) The outdoor meter is read monthly by a meter reader, and b) The soil over the underground gas service line in the immediate area of the meter, for a distance of ten feet and a width of two - three feet, has obviously been disturbed by digging, and is noticeable to anyone who approaches the meter, and c) Three or four monthly meter readings are made between the time of the digging and the time that an explosion and fire occur as a result of a leak in the underground gas service line within five feet of the meter? 8. Knowing that the natural gas distribution system's odorant will be absorbed by the passage of natural gas through soil if a leak occurs underground, what duty does an operator have under sec. 192.751 to post warning signs to minimize the danger of accidental ignition of gas in occupied structures alongside of which an underground service line runs? For example, does the operator have a duty to warn the occupant-customer that digging near the service line might cause a leak that won't be detectable by smell? Thank you for your kind assistance in this matter. Sincerely, James D. Shelby#