You are here

Interpretation Response #PI-76-037

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

Interpretation Response Details

Response Publish Date: 07-14-1976
Company Name: Northwest Pipeline Corporation    Individual Name: John M. Viehweg
Location state: UT    Country: US

View the Interpretation Document

Response text:

Jul 14 1976

Mr. John M. Viehweg
Chief Engineer
Northwest Pipeline Corporation
P.O. Box 1526
Salt Lake City, UT 84110

Dear Mr. Viehweg:

This responds to your letter of April 28, 1976, informing us of you plans for additional LNG facilities and asking for clarifications regarding standards incorporated by reference in 49 CFR Part 192. As you are aware, Mr. Beheshti of your company discussed these issues with this Office earlier in April. At that time, a copy of the Federal "Regulations for the Transportation of Natural and Other Gas by Pipeline," 49 CFR Parts 191 and 192, and all subsequent amendments were forwarded to you.

Your first question asks if adoption of NFPA 59A-1975 is likely in the near future.

Answer: Amendment 192-22, "Incorporation by Reference," shows that the 1972 edition of NFPA 59A will become the referenced standard effective July 1, 1976. Because we are presently developing independent Federal regulations for LNG facilities, it is unlikely that the 1975 edition will be adopted. However, for planning your new facilities, you may wish to consider that the LNG regulations propose to include or exceed any more stringent requirements set forth by the NFPA 59A-1975 edition.

Your following Questions 2 through 5 cite specific examples where a standard which is incorporated by reference in Appendix A in turn incorporates other standards by reference. Because the criteria which you request in Question 5 also applies to your other questions, it is presented at this point as follows:


Where conformance with applicable requirements of a referenced standard is set forth as a regulation under Part 192, only the specific edition cited in Appendix A has the standing of a Federal regulation.

Where standards are incorporated in turn through a chain of references originating from applicable requirements of the standard first referenced, the appropriate edition is determined as follows:

(a) If the standard is also referenced in Appendix A and is applicable for the same purposes as prescribed by Part 192, then the edition specified in Appendix A is the Federal regulation.

(b) If, however, the standard is not referenced in Appendix A, or is referenced in Appendix A but is applicable for purposes other than as prescribed by Part 192, then either the edition specified in the reference chain, or if not specified, the edition that would have been in effect on the effective date of the referential standard, is the appropriate referent standard.

Question 2 asks if either edition may be used when the specified edition of a referent standard incorporated through a chain of references differs from the edition referenced in Appendix A.

Answer: No, only one is applicable as determined by the foregoing criteria.

In Question 3 the circumstances are similar, except that the referent standard is not referenced in Appendix A, and you ask if a later edition than that which is specified may be used.

Answer: No, because the later standard has not been subject to necessary rule-making procedures. Criteria set forth in paragraph (b) above applies to this determination.

Question 4 is similar to Question 3, except that the edition of the referent standard incorporated through a chain of references is not specified by the referential standard but is referenced in Appendix A, and asks if a later edition than that which is specified in Appendix A may be used.

Answer: In accordance with the criteria, if the standard referenced in both Appendix A and a reference chain is applicable for the same purpose, then the edition referenced in Appendix A must be used, and the answer to your question is "no." If, however, a reference chain incorporates a standard for prescribing requirements which are not applicable to the regulations of Part 192, then the reference standard must be a particular edition, which may be either an earlier or later edition than that referenced in Appendix A, as determined by the criteria.

Question 5 asks when a standard referenced in Appendix A successively incorporates a standard which in turn incorporates another standard and referent standards are neither specified by edition nor referenced in Appendix A, what criteria should an operator use in determining the applicable edition?

Answer: The criteria requested is presented earlier. Determination of the appropriate edition of the referent standard is accordingly dependent on applicability and not necessarily on being referenced in Appendix A.

Question 6 asks if addenda or revisions to the applicable edition of a standard may be used.

Answer: Concordant with the answer to Question 3, such modifications may not be used unless specifically incorporated by reference.

We trust this satisfactorily answers your questions and thank you for your interest in pipeline safety.


Cesar DeLeon
Acting Director
Office of Pipeline
Safety Operations

Regulation Sections

Section Subject
§ 192.7 What documents are incorporated by reference partly or wholly in this part?