Interpretation Response #PI-03-0105 ([Commonwealth of Pennsylvania Public Utility Commission Bureau of Transportation and Safety] [Mr. Paul Metro])

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

Interpretation Response Details

Response Publish Date: 06/11/2003

Company Name: Commonwealth of Pennsylvania Public Utility Commission Bureau of Transportation and Safety

Individual Name: Mr. Paul Metro

Location State: PA Country: US

View the Interpretation Document

Response text:

PI-03-0105

U. S. Department of Transportation
Research and Special Programs Administration
400 Seventh St., S.W.
Washington, D.C. 20590

June 11, 2003

Mr. Paul Metro
Supervisor, Gas Safety Division
Pennsylvania Public Utility Commission
Bureau of Transportation and Safety
400 North Street, 300 Barto
Harrisburg, PA 17105-3265

Dear Mr. Metro:

This is in response to your request of January 29, 2002, for an interpretation of the gas pipeline safety regulations at 49 CFR 192.59(b)(3) related to the reuse of polyethylene pipe.

PPL Gas Utilities Corporation (PPL) intends to convert a polyethylene distribution system from propane vapor service to natural gas service, and has requested an interpretation. PPL's position is that:

. . . in accordance with § 192.11, Petroleum gas systems, the propane distribution system is already subject to Part 192. New polyethylene pipe was installed in 1988, and met the requirements of § 192.11, along with the requirements of § 192.50(a). Because the piping system is already qualified under § 192.59(a), the plastic pipe should not be considered "used" and subject to both § 192.59(a) and § 192.5(b).

PPL recognizes that liquid propane can have an effect on plastic pipe, including possible problems with fusibility. They also note that the system has been operated in accordance with 49 CFR Part 192, "Transportation of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards," and ANSI/NFPA 58, "Standard for the Storage and Handling of Liquefied Petroleum Gases," which limits the operating pressure of polyethylene piping carrying propane to 30 psig. The PPL system has been operating at a pressure of 10 psig, which would not result in deleterious condensation.

There is no question that the piping in question has been transporting propane vapor and that such service has been subject to 49 CFR Part 192. Therefore, the only question is whether use of this piping system for natural gas service is allowable under § 192.59(b)(3). This section allows the use of used plastic pipe for natural gas service if it was manufactured in accordance with a listed specification, if it is resistant to chemicals, if it is free of visible defects, if its dimensions are still within tolerances of the specification to which it was manufactured, and if it has been used only in natural gas service.

We do not consider changing the gas service from propane vapor to natural gas for pipe that has always been in compliance with 49 CFR Part 192 to constitute the use of "used plastic pipe" as contemplated in § 192.59(b)(3). Therefore, conversion of a jurisdictional polyethylene plastic distribution system from propane vapor service to natural gas service is acceptable.

If you have any further questions about the pipeline safety regulations, please contact me at (202) 366-4565.

Sincerely,

Richard D. Huriaux, P.E.
Manager, Regulations
Office of Pipeline Safety

Regulation Sections