GLOSSARY
To understand this manual, operators of small natural gas systems need to know the meaning of some commonly used terms. The terms are defined below for the purpose of this guidance manual. The reader is referred to 49 CFR Parts 191 and 192 for additional definitions.
ANNUALLY – means at intervals not exceeding 15 months, but at least once each calendar year.
CATHODIC (CORROSION) PROTECTION – a procedure by which underground metallic pipe is protected against deterioration (rusting and pitting). Basic theory, concepts, and practical considerations for cathodic protection are contained in Chapter III.
CUSTOMER METER – a device that measures the volume of gas transferred from an operator to the consumer.
DOWNSTREAM – any point in the direction of flow of a gas from the reference point.
EMERGENCY PLAN – written procedures for responding to emergencies on the pipeline system.
GAS OPERATOR – a gas operator may be a gas utility company, a municipality, or an individual operating a housing project, apartment complex, condominium, or a mobile home park served by a master meter. The operator is ultimately responsible for complying with the pipeline safety regulations.
HIGH-PRESSURE DISTRIBUTION SYSTEM – a distribution system in which the gas pressure in the main is higher than the pressure provided to the customer; therefore, a pressure regulator is required on each service to control pressure to the customer.
INCIDENT – an event that involves a release of natural gas from a pipeline facility that results in:
(1) a death or personal injury necessitating in-patient hospitalization; (2) estimated property damage of $50,000 or more; or (3) an event that the operator deems significant (check with your local state authorities for additional requirements, APPENDIX C).
LOW-PRESSURE DISTRIBUTION SYSTEM – a distribution system in which the gas pressure in the main is substantially the same as the pressure provided to the customer; normally a pressure regulator is not required on individual service lines.
MAIN – a natural gas distribution pipeline that serves as a common source of supply for more than one service line.
MASTER METER SYSTEM – a natural gas pipeline system for distributing natural gas for resale within, but not limited to, a distinct area, such as a mobile home park, housing project, or apartment complex, where the operator purchases metered gas from an outside source. The natural gas distribution pipeline system supplies the ultimate consumer who either purchases the gas directly through a meter or by other means such as by rent.
MAXIMUM ALLOWABLE OPERATING PRESSURE (MAOP) – the maximum pressure at which a pipeline may be operated in compliance with the gas pipeline safety regulations. It is established by design, past operating history, pressure testing, and pressure ratings of components.
MUNICIPALITY – a city, county, or any other political subdivision of a state.
NATURAL GAS – a non-toxic, colorless fuel, about one-third lighter than air. Natural gas burns only when mixed with air in certain proportions and ignited by a source of ignition (spark or flame) (Figure IV-4). Natural gas in its natural state may not have an odor.
OPERATING AND MAINTENANCE PLAN – written procedures for operations and maintenance on natural gas pipeline systems.
OVERPRESSURE PROTECTION EQUIPMENT – equipment installed to protect and prevent pressure in a system from exceeding the maximum allowable operating pressure (MAOP).
PIPELINE – all facilities through which gas moves in transportation. This includes pipes, valves, and other items attached to the pipe, meter stations, regulator stations, delivery stations, holders, and fabricated assemblies.
PRESSURE REGULATING/RELIEF STATION – a device to automatically reduce and control the gas pressure in a pipeline downstream from a higher pressure source of natural gas. It includes any enclosures, relief devices, ventilating equipment, and any piping and auxiliary equipment, such as valves, regulators, control instruments, or control lines.
PRETESTED PIPE – pipe that has been tested by the operator to 100 psig for at least one hour.
SERVICE LINE – a natural gas distribution line that transports gas from a common source of supply to a customer's meter, or to the connection to a customer's piping if the piping is farther downstream or if there is no meter.
SERVICE REGULATOR – a device designed to reduce and limit the gas pressure provided to a customer.
SERVICE RISER – the section of a service line which extends out of the ground and is often near the wall of a building. This usually includes a shut-off valve and a service regulator.
SHUT-OFF VALVE – a valve used to stop the flow of gas. The valve may be located upstream of the service regulator or below ground at the property line or where the service line connects to the main.
UPSTREAM – from a reference point, any point located nearest the origin of flow, that is, before the reference point is reached.
49 CFR – Title 49 of the Code of Federal Regulations (CFR). This document contains the actual
safety regulations that must be complied with by the natural gas operator. Parts 190, 191, 192,
and 199 of 49 CFR contain the federal pipeline safety regulations relevant to operators of natural
gas pipeline systems.
COMMONLY ABBREVIATED ORGANIZATION/ACRONYMS
AGA – American Gas Association.
ANSI – American National Standards Institute, formerly the United States of America Standards Institute (USASI). All current standards issued by USASI and American Standard Association
(ASA) have been redesignated as American National Standards Institute and continue in effect.
APGA – American Public Gas Association.
API – American Petroleum Institute.
ASME – American Society of Mechanical Engineers.
ASTM – American Society for Testing and Materials.
DOT – U.S. Department of Transportation.
GPTC – Gas Piping Technology Committee.
INGAA – Interstate Natural Gas Association of America.
MEA – Midwest Energy Association.
MSS – Manufacturers Standardization Society of the Valve and Fittings Industry.
NACE – National Association of Corrosion Engineers. (NACE International)
NFPA – National Fire Protection Association.
OPS – Office of Pipeline Safety. The pipeline safety division of the DOT’s Pipeline and Hazardous Materials Safety Administration. For addresses of OPS regional offices, see the attached list of agencies and organizations.
PHMSA – Pipeline and Hazardous Materials Safety Administration. A major subdivision of the DOT, it includes the Office of Pipeline Safety. For addresses of regional offices, see the enclosed handout.
SGA – Southern Gas Association.
