West Virginia Public Service Commission — Pipeline Safety Interpretation

Page 1PI-73-0106 Mar 22 1973 Mr. T. K. Spalding Director, Gas Pipeline Safety Division West Virginia Public Service Commission Capitol Building Charleston, West Virginia 25305 Dear Mr. Spalding: This is in response to your letter of February 22, 1973, to Frank Fulton in which you asked if the Federal Minimum Safety Standards permit the use of approved plastic pipe for mains and service lines to distribute LPG from a central point in a mobile home park. The Federal Minimum Safety Standards contained in 49 CFR, Part 192, Transportation of Natural and Other Gas by Pipeline permit the use of plastic pipe in mains and services with certain limitations. These limitations in general, relate to the operating temperature and pressure, and the chemical compatibility of the pipe to the product to be carried. The major concern over using plastic in a LPG system is that of condensation in the LPG vapor. This condensation may result in a decrease of the physical and chemical properties of certain plastic pipes. Therefore, if there is any possibility of condensation of the LPG vapor in the piping system then the pipe selected must be capable of retaining its integrity with the liquid in the line. It is the operator's responsibility to assure the integrity of the plastic pipe selected for use in the piping system and this should be based on a favorable recommendation by the manufacturer. Therefore, the Federal Minimum Safety Standards do permit the use of plastic in a properly engineered underground system of LPG distribution conforming to the limitations of these regulations. I trust this information will clarify this matter for you. If we can be of any further assistance, please advise. Sincerely, Joseph C. Caldwell Director Office of Pipeline Safety#

Page 2State of West Virginia Public Service Commission Charleston, 25305 February 22, 1973 Mr. Frank Fulton, Chief Technical Section Office of Pipeline Safety Department of Transportation Washington, D. C. 20590 Dear Frank: Please advise if the minimum safety standards permit the use of approved plastic pipe for mains and service lines to distribute LPG from a central point in a mobile home park. We have had one request for an answer to that question and it will probably become an increasingly important problem. Last year this state issued construction permits for 79 mobile home parks containing 1,712 spaces. With the scarcity of natural gas and consequent expanded use of LPG, we should be in a position to advise operators on the use of plastic. Yours very truly, T. K. Spalding, Director Gas Pipeline Safety Division#