{"operation":"document","citation":"PI-92-034","title":"Virginia State Corporation Commission — Pipeline Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"1992-07-23","effective_on":null,"summary":"PI-92-034 response to Virginia State Corporation Commission concerning 192.175, 192.177, 192.619, 192.621, 192.743.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-92-034.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-92-034.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-92-034","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/Pipeline/1992/PI92034.pdf","body":"<<<PAGE 1>>>\n\nJuly 23, 1992\nMr. Massoud Tahamtani\nUtilities Manager\nDivision of Energy Regulation\nVirginia State Corporation Commission\nP.O. Box 1197\nRichmond, VA 23209\nDear Mr. Tahamtani:\nThis responds to your letter of June 29, 1992, asking questions about Part 192.\nFirst, you asked if gas storage vessels used with a valve actuator are bottle-type holders subject to\n§§ 192.175 and 192.177. These two standards are based on comparable provisions of the 1968\nedition of ASME B31.8 Code. That Code contains the following definitions:\nBottle-type holder is any bottle or group of interconnected bottles installed in one\nlocation, and used for the sole purpose of storing gas.\nBottle * * * is a gas-tight structure completely fabricated from pipe with integral drawn,\nforged, or spun end closures and tested in the manufacturer's plant.\nBased on these definition, we believe the vessels are not bottle-type holders. Although they may\nbe bottles that store gas, gas storage is not their sole purpose. The fact, their primary purpose is\nto provide power to actuate the valve when necessary. Thus, they are not subject to §§ 192.175\nand 192.177.\nNext, you asked whether a city gate station must have overpressure protection. If it is required,\nyou asked whether the station operator may reply on an interstate transmission operator's devices\nto protect the station against overpressure. If such reliance is permissible, you asked if you may\nrequest from the station operator information about the devices to demonstrate compliance with\napplicable standards, such as § 192.743.\nUnder Part 192, distribution systems readied for service after March 12, 1971, or replaced,\nrelocated, or otherwise changed after November 12, 1970, must have overpressure protection\ndevices under § 192.195. Other distribution systems are not required to have such protection\nunless their maximum allowable operating pressure is established under § 192.619(b) or §\n192.621(b). If a distribution operator seeks to satisfy these requirements by relying on\noverpressure protection devices it does not own or operate, it is still responsible for compliance of\nthe devices with Part 192. In this case, you may ask the operator to produce evidence that the\ndevices comply with applicable Part 192 requirements.jt 1\n192.175/92-07-23\n\n<<<PAGE 2>>>\n\nFinally, you asked if § 192.625(a) may be met by collecting gas samples throughout a system,\ntesting the samples for odorant concentration with a gas chromatograph, and reporting\nconcentrations of odorant in gas as lbs./MMCF. If so, you asked at what odorant concentration\n(lbs./MMCF) would a gas in air concentration of one-fifth of the lower explosive limit be readily\ndetectable by a person with a normal sense of smell.\nSection 192.625(a) provides that a combustible gas in a distribution line must contain a natural\nodorant or be odorized so that at a concentration in air of one-fifth of the lower explosive limit,\nthe gas is readily detectable by a person with a normal sense of smell. Also, § 192.625(f) provides\nthat each operator shall conduct periodic sampling of combustible gases to assure the proper\nconcentration of odorant. Section 192.625 does not specify how an operator must test the\nsamples to assure that a pipeline contains the proper concentration of odorant, or the\nconcentration required by § 192.625(a). So any testing procedure may be used that is capable of\ndemonstrating the sufficiency of odorant concentration. If a gas chromatograph is used, the\noperator must compare the measured odorant concentrations with the proper concentration,\nwhich must be determined separately. Since the proper odorant concentration can vary among\nsystems, we cannot give you a specific value in lbs./MMCF that meets the standard.\nI hope you find this information useful. If you need any further clarification, please call me.\nSincerely,\nCesar De Leon\nDirector, Regulatory Programs\nOffice of Pipeline Safety\njt 2\n192.175/92-07-23","truncated":false,"body_characters":3954}