In this subtitle the following terms have the meanings indicated. Terms Defined. Abbreviations. “Btu” means British thermal unit. “LNG” means liquefied natural gas. “LPG” means liquefied petroleum gas. “PSIG” means pounds per square inch, gauge. “W.C.” means water column. “Accuracy” means the degree of conformity of a measure to a standard or true value. “Check flow” means a flow between 20 percent and 50 percent of the rated capacity of a meter. “Commission” means the Public Service Commission of Maryland. “Cubic foot” of gas means: Where gas is supplied and metered to customers at the pressure normally maintained on residential customers' meters, a cubic foot of gas is that quantity of gas which, at the temperature and pressure existing in the meter, occupies 1 cubic foot. Where gas is supplied and measured with corrections made for pressure or temperature conditions, or both, existing in the meter, a cubic foot of gas is that quantity of gas which occupies a cubic foot after the metered quantity has been corrected to the absolute pressure or the temperature, or both, specified in the utility's tariff (see COMAR 20.55.03.01B(8)). The standard cubic foot of gas for testing the gas itself for heating value shall be that quantity of gas, saturated with water vapor, which at a temperature of 60°F and a pressure of 30 inches of mercury occupies 1 cubic foot. (Temperature of mercury = 32°F; acceleration due to gravity = 32.17 feet per second per second; density of mercury = 13.595 grams per cubic centimeter.) “Customer” means a person, partnership, association, corporation, or governmental agency being supplied with gas service and whose name appears on the application for service. “Division” means the Engineering Division of the Commission. “Full rated flow” means a flow of approximately 100 percent of the rated capacity of a meter. “Gas master meter operator” has the meaning stated in Public Utilities Article, §1-101, Annotated Code of Maryland. “Gas plant” or “pipeline facility” means new and existing pipelines, rights-of-way, and any equipment, facility, or building used in the transportation of gas or in the treatment of gas during the course of transportation. “Incident” has the meaning stated in 49 CFR §191.3, as amended, which is incorporated by reference. “Main” means a distribution line that serves as a common source of supply for more than one service line. “Meter”, without other qualification, means a device which is used by a utility in measuring a quantity of gas. “Percent accuracy” means the ratio expressed in percent of the meter indicated volume (numerator) to the prover or other working standard volume (denominator) obtained in volumetric testing of gas meters. “Percent proof” means the ratio expressed in percent of the prover or other working standard volume (numerator) to the meter indicated volume (denominator) obtained in volumetric testing of gas meters. “Pipeline” means all parts of those physical facilities through which gas moves in transportation, including pipe, valves, and other appurtenances attached to pipe, compressor units, metering stations, regulator stations, delivery stations, holders, and fabricated assemblies. “Places of public assembly” means a building or portions of a building used for gathering together of 100 or more persons, the capacity being designated by the fire department for common purposes of deliberation, worship, or services, such as but not limited to churches, schools, hospitals, halls, theaters, and municipal facilities. “Premises” means a tract of land or real estate, including buildings and other appurtenances on it. “Rated capacity of a meter” means the capacity of the meter as specified by the manufacturer under the conditions of use. “Service line” means a gas pipe owned, operated, or maintained by a utility that runs from a main or a pipeline to the meter serving a customer. “Utility” or “company” means any gas company operating under the jurisdiction of the Commission. “Working standard” means the prover, test meter, or other approved device used to test customer meters or associated devices, or both.