San Diego Gas & Electric Company — Pipeline Safety Interpretation

Page 1PI-74-0157 December 27, 1974 Mr. Paul L. Hathaway Vice President San Diego Gas & Electric Company P. O. Box 1831 San Diego, CA 92112 Dear Mr. Hathaway: In your letter of November 7, 1974, you asked for the Office of Pipeline Safety's evaluation of three types of service risers being used in the San Diego area on privately owned gas systems. It appears that there is a misunderstanding of the criteria for determining whether a facility is subject to the requirements of Part 192. Your statement that, "Many of these private systems are master metered or HUD financed, and are, therefore, subject to the Department of Transportation's Minimum Safety Standards for gas" is not necessarily accurate. The applicability of 49 CFR Part 192 in these master meter systems depends upon whether or not the gas is still in transportation and thus upon who is consuming the gas, the owner of the project or the individual tenants. Under 49 CFR 192.3 an "Operator" is defined as "a person who engages in the transportation of gas." The term "transportation of gas" is defined as "the gathering, transmission, or distribution of gas by pipeline . . . “The term "pipeline" is defined as "all parts of those physical facilities through which gas moves in transportation. . . . If the owner of the piping downstream of the master meter is the consumer of the gas, as in the case of centrally located systems, to provide heating, air conditioning, hot water, etc., then he is not transporting the gas and is thus not an operator subject to Department of Transportation (DOT) regulations. If, however, the gas is being delivered to and consumed by others in the complex, then the gas is being transported and the owner of the piping downstream of the master meter does become an operator subject to DOT regulations. The risers in Figures 1 and 2 appear to be of conventional design, but these sketches do not give sufficient detail to determine compliance with Part 192. Assuming that the materials in these risers meet the requirements of Part 192, the operator still must comply with design, construction, operation, maintenance, and corrosion control requirements. Figure 3 indicates a pipe diameter of 4 inches. This size would either be used as a service riser to supply a customer with a large amount of gas or as part of a main to connect a master meter to the downstream piping. If the riser is used on a service line, it would not comply with Section 192.375(a)(1), which requires that the above ground part of a plastic service line he protected against deterioration and external damage. As shown in Figure 3, the PVC flange is exposed. On the other hand, if the riser is used as part of a main, its installation would be prohibited by Section 192.321(a), which requires that plastic pipe be installed below ground level. Thank you for your interest in pipeline safety. Sincerely, Original signed by: Joseph C. Caldwell Director Office of Pipeline Safety#

Page 2November 7, 1974 San Diego gas & Electric Company P.O. Box 1831 San Diego, California 92112 Mr. Joseph C. Caldwell, Director Office of Pipeline Safety Washington, D. C. 20590 Dear Mr. Caldwell: In the San Diego area, PVC plastic pipe is being used in an increasing number of privately-owned (non-utility) gas systems as a substitute for steel. Many of these private systems are master metered or HUD financed, and are, therefore, subject to the Department of Transportation's Minimum Safety Standards for gas. We are requesting a ruling concerning the acceptability of three types of risers for use on private systems subject to the OPS regulations. The risers shown in Figures 1 and 2 are commonly used by private systems in the San Diego area. The use of design No. 3 has prompted discussion among interested parties concerning its acceptability to OPS. Some of the considerations which have been mentioned in discussing design No. 3 include: A. An all-plastic system will not be subject to corrosion. On a privately-owned system employing steel pipe, cathodic protection may not be properly installed or maintained, leading to leakage from corrosion. B. The required thermal and mechanical protection for above-ground plastic pipe is believed to be provided by a schedule 80 PVC sleeve anchored in a concrete pad, as shown in Figure 3. C. Paragraph 192.375 permits a plastic "service line" to terminate above ground. D. Paragraph 192.321(a) prohibits plastic "mains" above ground. Please advise us which of the riser designs shown in Figures 1, 2 and 3 are acceptable for use above ground to connect a privately-owned line to a utility master meter as shown in Figure 4. Yours very truly, Paul L. Hathaway#