This Glossary was compiled to respond to our over 20 years of work with local communities seeking answers to questions about pipeline construction, engineering, and safety. The definitions found here are taken from regulatory and technical sources, including the 2016 PIPES Act. If you cannot find what you are looking for in our Glossary try ASTM International’s Pipeline Glossary.
Abandoned – A pipeline permanently removed from service.
Abnormal Operating Condition – A condition identified by the operator that may indicate a malfunction of a component or deviation from normal operations that may indicate a condition exceeding design limits, or result in a hazard(s) to persons, property, or the environment.
Accident – Failures occurring in liquid pipeline systems for which the pipeline operator must make a report to the Office of Pipeline Safety. Specific criteria defining events that are considered accidents are contained in 49CFR 195.50. Events or failures of similar magnitude related to gas pipelines are considered incidents and are defined in 49 CFR 191.3.
Alarm – An audible or visible means of indicating to the controller that equipment or processes are outside operator-defined, safety-related parameters.
Anomaly – Imperfection, defect, or critical defect in the wall of the pipe.
Area Contingency Plan (ACP) – A reference document prepared for the use of all agencies engaged in responding to environmental emergencies within a defined geographic area. An ACP may also contain Sub-Area and Geographic Response Plans, which may have more limited scope than the ACP itself. An ACP is a mechanism to ensure that all emergency responders have access to essential area-specific information and promotes inter-agency of coordination to improve the effectiveness of responses.
Barrel – 42 United States gallons (159 liters) at 60 degrees Fahrenheit (15.6 degrees Celsius).
Blow Down – Scheduled and unscheduled releases of gas from compressor stations. According to PHSMA protocol (49 CFR 192.605), operators are required to create and maintain a procedural manual for maintenance and to follow protocol for scheduled blow downs. These procedures and protocol vary by company.
Breakout Tank – A tank used to: (1) Relieve surges in an oil pipeline system, or (2) Receive and store oil transported by a pipeline for reinjection and continued transportation by pipeline.
British Thermal Unit (Btu) – A measure of the heat content of fuels or energy sources. It is the quantity of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at the temperature that water has its greatest density (approximately 39 degrees Fahrenheit). One British thermal unit (Btu) is approximately equal to the energy released by burning a match.
Carbon Dioxide – A fluid consisting of more than 90 percent carbon dioxide molecules compressed to a super-critical state.
Cathodic Protection – An electrochemical process to control the corrosion of a metal surface by transferring the corrosion from the protected structure to a more easily corroded metal. A critical component of corrosion mitigation.
Class Location (also see Class Location Unit)- Criterion for pipeline location and design set by 49 CFR 192 ranging from Class 1, rural areas to Class 4, heavily populated urban areas. Class location is based on the number and type of buildings in an area that extends 220 yards on either side of the center line of any continuous 1-mile length of a pipeline. A Class 4 location ends 220 yards (200 meters) from the nearest building with four or more stories above ground. When a cluster of buildings intended for human occupancy requires a Class 2 or 3 location, the class location ends 220 yards (200 meters) from the nearest building in the cluster.
Class 1 Location – An offshore area, or any class location unit that has 10 or fewer buildings intended for human occupancy.
Class 2 Location – Any class location unit that has more than 10 but fewer than 46 buildings intended for human occupancy.
Class 3 Location – Any class location unit that has 46 or more buildings intended for human occupancy, or an area where the pipeline lies within 100 yards (91 meters) of either a building or a small, well-defined outside area (such as a playground, recreation area, outdoor theater, or other place of public assembly) that is occupied by 20 or more persons on at least 5 days a week for 10 weeks in any 12-month period. (The days and weeks need not be consecutive.)
Class 4 Location – Any class location unit where buildings with four or more stories above ground are prevalent.
Class Location Unit – An onshore area that extends 220 yards (200 meters) on either side of the center line of any continuous one mile (1.6 kilometers) length of pipeline.
Competent Authority – A national agency that is responsible, under its national law, for the control or regulation of some aspect of hazardous materials (dangerous goods) transportation. Another term for Competent Authority is “Appropriate authority,” which is used in the International Civil Aviation Organization’s (ICAO) Technical Instructions for the Safe Transport of Dangerous Goods by Air. The Associate Administrator is the United States Competent Authority for purposes of 49 CFR 107 (Hazardous Materials Program Procedures).
Component – Any part of a pipeline which may be subjected to pump pressure including, but not limited to, pipe, valves, elbows, tees, flanges, and closures.
Compression – The process of (1) increasing the pressure of gas to maintain its flow in a pipeline system, or (2) reducing the amount of data to be stored in an in-line inspection tool.
Computation Pipeline Monitoring (CPM) – A software-based monitoring tool that alerts the pipeline dispatcher of a possible pipeline operating anomaly that may be indicative of a commodity release.
Control Room – An operations center staffed by personnel charged with the responsibility for remotely monitoring and controlling a pipeline facility.
Controller – A qualified individual who remotely monitors and controls the safety-related operations of a pipeline facility via a SCADA system from a control room, and who has operational authority and accountability for the remote operational functions of the pipeline facility.
Corrosion, Active – Continuing corrosion that, unless controlled, could result in a condition that is detrimental to public safety.
Corrosion, General External – Metal loss on a pipe caused by electro-chemical, galvanic, microbiological, or impacts due to environmental conditions.
Corrosion, General Internal – Metal loss on a pipe caused by chemical or other impact on the steel from liquids inside the pipe.
Corrosion, Pit – External or internal corrosion on the surfaces that results from the generation of a potential (voltage) difference set up by variations in oxygen concentrations within and outside the pit.
Corrosion, Stress Cracking – A progressive cracking that results from a combination of tensile stress, cathodic protection currents, and a corrosive environment.
Corrosion, Significant Stress Cracking – A stress corrosion cracking (SCC) cluster in which the deepest crack, in a series of interacting cracks, is greater than 10% of the wall thickness and the total interacting length of the cracks is equal to or greater than 75% of the critical length of a 50% through-wall flaw that would fail at a stress level of 110% of SMYS.
Corrosive Product or Corrosive Material – A liquid or solid that causes full thickness destruction of human skin at the site of contact within a specified period of time. A liquid, or a solid which may become liquid during transportation, that has a severe corrosion rate on steel or aluminum based on the criteria in 49 CFR 173.137(c)(2) is also a corrosive material. Per 49 CFR 173.136 Class 8-Definitions of this chapter.
Covered Segment or Covered Pipeline Segment – A segment of gas transmission pipeline located in a high consequence area (HCA).
Customer Meter – The meter that measures the transfer of gas from an operator to a consumer.
Damage or Excavation Damage – Any excavation activity that results in the need to repair or replace a pipeline due to a weakening, or the partial or complete destruction, of the pipeline, including, but not limited to, the pipe, appurtenances to the pipe, protective coatings, support, cathodic protection or the housing for the line device or facility.
Decommissioning, Offshore Oil and Gas Facilities – The process of removing the infrastructure and equipment used in the exploration and production of oil and gas in the marine environment, including pipelines, wellheads, platforms, artificial islands, and power cables.
Direct Assessment – An integrity assessment method that utilizes a process to evaluate certain threats (i.e., external corrosion, internal corrosion and stress corrosion cracking) to a covered pipeline segment’s integrity. The process includes the gathering and integration of risk factor data, indirect examination or analysis to identify areas of suspected corrosion, direct examination of the pipeline in these areas, and post assessment evaluation.
Direct Assessment, Confirmatory – An integrity assessment method using more focused application of the principles and techniques of direct assessment to identify internal and external corrosion in a covered transmission pipeline segment. is an integrity assessment method using more focused application of the principles and techniques of direct assessment to identify internal and external corrosion in a covered transmission pipeline segment.
Distribution Line – A pipeline other than a gathering or transmission line.
DOT Procedures – The Procedures for Transportation Workplace Drug and Alcohol Testing Programs published by the Office of the Secretary of Transportation.
Dry vs. Wet Gas – Natural gas is considered ‘dry’ when it is almost pure methane, having had most of the other commonly associated hydrocarbons removed. When other hydrocarbons are present, the natural gas is ‘wet’.
Easement – Is the right to use the real property of another without possessing it. A right-of-way agreement between the pipeline company and the property owner is also called an easement and is usually filed in the public records with property deeds. A pipeline right-of-way is a strip of land over and around pipelines where some of the property owner’s legal rights have been granted to a pipeline company. Rights-of-ways and easements provide a permanent, limited interest in the land that enables the pipeline company to operate, test, inspect, repair, maintain, replace, and protect one or more pipelines on property owned by others. The agreement may vary the rights and widths of the right-of-way, but generally, the pipeline company’s right-of-ways extend 25 feet from each side of a pipeline unless special conditions exist.
Electrical Survey – A series of closely spaced pipe-to-soil readings over pipelines which are subsequently analyzed to identify locations where a corrosive current is leaving the pipeline.
Emergency – A deviation from normal operation, a structural failure, or severe environmental conditions that probably would cause harm to people or property (per 49 CFR 193).
Emergency Order – A written order from the Administrator of the Pipeline and Hazardous Materials Safety Administration, or his or her delegate, imposing restrictions, prohibitions, or safety measures on affected entities.
Environmentally Sensitive or Significant Areas (ESA) – A “sensitive area” identified in the applicable Area Contingency Plan (ACP), or if no applicable, complete ACP exists, an area of environmental importance which is in or adjacent to navigable waters.
Excavation or Excavation Activities – Blasting, boring, tunneling, back-filling, the removal of above ground structures by either explosive or mechanical means, and other earth-moving operations, and covers all excavation activity involving both mechanized and non-mechanized equipment, including hand tools.
Excavator – Any person or legal entity, public or private, proposing to or engaging in excavation.
Exclusion Zone – An area surrounding an LNG facility in which an operator or government agency legally controls all activities in accordance with 49 CFR 193.2057 and 193.2059 for as long as the facility is in operation.
Exposed Underwater Pipeline – An underwater pipeline where the top of the pipe protrudes above the underwater natural bottom (as determined by recognized and generally accepted practices) in waters less than 15 feet (4.6 meters) deep, as measured from mean low water.
Facility Response Plan (FRP) – A plan required of facilities that store and use oil and that demonstrates a facility’s preparedness to respond to a worst case scenario oil discharge. Administered through U.S. EPA through 40 CFR 112.20-21.
Fail-safe – A design feature which will maintain or result in a safe condition in the event of malfunction or failure of a power supply, component, or control device.
Failure – A condition in which a human, structure, component, device, or system fails to adequately perform its intended purpose; or The point at which the pipe material is stressed beyond its elastic or yield point. At that point the material is deformed and does not return to its original shape. A pipeline rupture is an example of this type of failure.
Flammable Product or Flammable Liquid – A liquid having a flash point of not more than 60 degrees Celsius, C (140 degrees Fahrenheit, F), or any material in a liquid phase with a flash point at or above 37.8 degrees C (100 degrees F) that is intentionally heated and offered for transportation or transported at or above its flash point in a bulk packaging, with the following exceptions: (1) Any liquid meeting one of the definitions specified in 49 CFR 173.115; (2) Any mixture having one or more components with a flash point of 60 degrees C (140 degrees F) or higher, that make up at least 99 percent of the total volume of the mixture, if the mixture is not offered for transportation or transported at or above its flash point; (3) Any liquid with a flash point greater than 35 degrees C (95 degrees F) that does not sustain combustion according to ASTM D 4206 (IBR, see §171.7 of this subchapter) or the procedure in appendix H of this part; (4) Any liquid with a flash point greater than 35 degrees C (95 degrees F) and with a fire point greater than 100 degrees C (212 degrees F) according to ISO 2592 (IBR, see §171.7 of this subchapter); (5) Any liquid with a flash point greater than 35 degrees C (95 degrees F) which is in a water-miscible solution with a water content of more than 90 percent by mass. Per 49 CFR 173.120 Class 3-Definitions of this chapter.
g – The standard acceleration of gravity of 9.806 meters per second2 (32.17 feet per second2)
Gas – Natural gas, flammable gas, or gas which is toxic or corrosive.
Gas Transmission Pipeline – Includes all parts of the physical facilities through which gas moves in transportation, including pipe, valves, and other appurtenance attached to pipe, compressor units, metering stations, regulator stations, delivery stations, holders, and fabricated assemblies.
Gathering Line, Gas – A pipeline that transports gas from a current production facility to a transmission line or main.
Gathering Line, Hazardous Liquids – A pipeline 219.1 mm (85⁄8 in) or less nominal outside diameter that transports petroleum from a production facility.
Hazard to Navigation, Gas and Hazardous Liquids – A pipeline where the top of the pipe is less than 12 inches (305 millimeters) below the underwater natural bottom (as determined by recognized and generally accepted practices) in waters less than 15 feet (4.6 meters) deep, as measured from the mean low water.
Hazardous Leak – A leak that represents an existing or probable hazard to persons or property and requires immediate repair or continuous action until the conditions are no longer hazardous.
Hazardous Liquid – Petroleum, petroleum products, anhydrous ammonia, or ethanol.
Hazardous Material – A substance or material that the Secretary of Transportation has determined is capable of posing an unreasonable risk to health, safety, and property when transported in commerce, and has designated as hazardous under section 5103 of Federal hazardous materials transportation law (49 U.S.C. 5103). The term includes hazardous substances, hazardous wastes, marine pollutants, elevated temperature materials, materials designated as hazardous in the Hazardous Materials Table (see 49 CFR 172.101), and materials that meet the defining criteria for hazard classes and divisions in part 173 of subchapter C of Chapter 49.
High Consequence Areas (HCA) – High consequence area means an area established by one of the methods described in paragraphs (1) or (2) of 49 CFR 192.903, where: Paragraph (1) is an area defined as: (i) A Class 3 location under 49 CFR 192.5; or (ii) A Class 4 location under 49 CFR 192.5; or (iii) Any area in a Class 1 or Class 2 location where the potential impact radius is greater than 660 feet (200 meters), and the area within a potential impact circle contains 20 or more buildings intended for human occupancy; or (iv) Any area in a Class 1 or Class 2 location where the potential impact circle contains an identified site, and Paragraph (2) is the area within a potential impact circle containing— (i) 20 or more buildings intended for human occupancy, unless the exception in paragraph (4) applies; or (ii) an identified site. Where a potential impact circle is calculated under either method (1) or (2) to establish a high consequence area, the length of the high consequence area extends axially along the length of the pipeline from the outermost edge of the first potential impact circle that contains either an identified site or 20 or more buildings intended for human occupancy to the outermost edge of the last contiguous potential impact circle that contains either an identified site or 20 or more buildings intended for human occupancy. If in identifying a high consequence area under paragraph (1)(iii) of this definition or paragraph (2)(i) of this definition, the radius of the potential impact circle is greater than 660 feet (200 meters), the operator may identify a high consequence area based on a prorated number of buildings intended for human occupancy with a distance of 660 feet (200 meters) from the center line of the pipeline until December 17, 2006. If an operator chooses this approach, the operator must pro- rate the number of buildings intended for human occupancy based on the ratio of an area with a radius of 660 feet (200 meters) to the area of the potential impact circle (i.e., the prorated number of buildings intended for human occupancy is equal to 20 × (660 feet) [or 200 meters]/potential impact radius in feet [or meters]).
High-Pressure Distribution System – A distribution system in which the gas pressure in the main is higher than the pressure provided to the customer.
High Volume Area – An area which an oil pipeline having a nominal outside diameter of 20 inches (508 millimeters) or more crosses a major river or other navigable waters, which, because of the velocity of the river flow and vessel traffic on the river, would require a more rapid response in case of a worst case discharge or substantial threat of such a discharge. Appendix B in 49 CFR 194 contains a list of some of the high volume areas in the United States.
Highly Volatile Liquid (HVL) – A hazardous liquid which will form a vapor cloud when released to the atmosphere and which has a vapor pressure exceeding 276 kPa (40 psia) at 37.8 °C (100 °F).
Hydrostatic Testing – Testing of sections of a pipeline by filling the line with water and pressurizing it until the nominal hoop stresses in the pipe reach a specified value.
Identified Site – An outside area or open structure that is occupied by twenty (20) or more persons on at least 50 days in any twelve (12)-month period. (The days need not be consecutive.) Examples include but are not limited to, beaches, playgrounds, recreational facilities, camping grounds, outdoor theaters, stadiums, recreational areas near a body of water, or areas outside a rural building such as a religious facility; a building that is occupied by twenty (20) or more persons on at least five (5) days a week for ten (10) weeks in any twelve (12)-month period. (The days and weeks need not be consecutive.) Examples include, but are not limited to, religious facilities, office buildings, community centers, general stores, 4-H facilities, or roller skating rinks; or a facility occupied by persons who are confined, are of impaired mobility, or would be difficult to evacuate. Examples include but are not limited to hospitals, prisons, schools, day-care facilities, retirement facilities or assisted-living facilities.
Imminent Hazard – The existence of a condition which presents a substantial likelihood that death, serious illness, severe personal injury, or substantial endangerment to health, property, or the environment may occur before the reasonably foreseeable completion of an administrative hearing or other formal proceeding initiated to abate the risks of those effects.
Impounding System – Includes an impounding space (volume of space formed by dikes and floors which is designed to confine a spill of hazardous liquid) designed for conducting the flow of spilled hazardous liquids.
Incident – An event that is reported to U.S. Department of Transportation Office of Pipeline Safety that involves fatalities, injuries, property damage in excess of $50,000, unintentional release of natural gas, customer outages, or other conditions that, in the opinion of the pipeline operator, are significant enough that they should be reported. Also, any event resulting in the unintended and unanticipated release of a hazardous material or an event meeting incident reporting requirements in 49 CFR 171.15 or 171.16.
Indian (see Indigenous Peoples) – Term used by U.S. government and Department of Transportation per 25 U.S.C. § 450b. A person who is a member of an “Indian tribe.” ‘‘Indian tribe’’ means any Indian tribe, band, nation, or other organized group or community, including any Alaska Native village or regional or village corporation as defined in or established pursuant to the Alaska Native Claims Settlement Act (85 Stat. 688) [43 U.S.C. 1601 et seq.], which is recognized as eligible for the special programs and services provided by the United States to Indians because of their status as Indians.
Indigenous Peoples (see Indian) – Term used by Pipeline Safety Coalition. Peoples in independent countries who are regarded as indigenous on account of their descent from the populations which inhabited the country, or a geographical region to which the country belongs, at the time of conquest or colonization or the establishment of present state boundaries and who, irrespective of their legal status, retain some or all of their own social, economic, cultural and political institutions. Self-identification as indigenous or tribal shall be regarded as a fundamental criterion for determining indigenous peoples. This definition is derived from Article 1 (1b) of the International Labor Organisation’s Convention concerning Indigenous and Tribal Peoples (ILO No. 169) and the .
Injury, Environmental – A measurable adverse change, either long- or short-term, in the chemical or physical quality or the viability of a natural resource resulting either directly or indirectly from exposure to a discharge, or exposure to a product of reactions resulting from a discharge. (40 CFR 112)
In-Line Inspection (ILI) – The inspection of a pipeline from the interior of the pipe using an in-line inspection tool. In-Line Inspection Tool (ILI Tool): Device or vehicle, also known as an intelligent or smart pig, that inspects the wall of a pipe.
In-Plant Piping System – Piping that is located on the grounds of a plant and used to transfer hazardous liquid or carbon dioxide between plant facilities or between plant facilities and a pipeline or other mode of transportation, not including any device and associated piping that are necessary to control pressure in the pipeline under 49 CFR 195.406(b).
Integrity Management Plan or IM Plan – A written explanation of the mechanisms or procedures that a gas distribution system operator will use to implement its integrity management program and to ensure compliance with 49 CFR 192.
Integrity Management Program or IM Program – An overall approach by a gas distribution system operator to ensure the integrity of its gas distribution system.
Interstate Pipeline – A pipeline or that part of a pipeline that is used in the transportation of hazardous liquids, carbon dioxide, NVLs, or gas in interstate or foreign commerce.
Intrastate Pipeline – A pipeline or that part of a pipeline that is used in the transportation of hazardous liquids, carbon dioxide, NVLs, or gas that is not an interstate pipeline.
Landman – A representative of the gas or pipeline company.
Landman Authority – As a representative of the gas or pipeline company, a landman has limited authority in negotiating a Right of Way on your land.
Line Section, Gas – A continuous run of transmission line between adjacent compressor stations, between a compressor station and storage facilities, between a compressor station and a block valve, or between adjacent block valves.
Line Section, Hazardous Liquids and LNG – A continuous run of pipe that is contained between adjacent pressure pump stations, between a pressure pump station and a terminal or breakout tank, between a pressure pump station and a block valve, or between adjacent block valves.
Liquid – A material, with a melting point or initial melting point of 20 degrees C (68 degrees F) or lower at a standard pressure of 101.3 kPa (14.7 psia). A viscous material for which a specific melting point cannot be determined must be subjected to the procedures specified in ASTM D4359-90 “Standard Test Method for Determining Whether a Material is Liquid or Solid” (ANSI IBR, see 49 CFR 171.7).
Liquefied Natural Gas or LNG – Natural gas or synthetic gas having methane (CH4) as its major constituent which has been changed to a liquid.
LNG Facility – A pipeline facility that is used for liquefying natural gas or synthetic gas or transferring, storing, or vaporizing liquefied natural gas.
LNG Plant – An LNG facility or system of LNG facilities functioning as a unit.
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.
Low-Stress Pipeline – A hazardous liquid pipeline that is operated in its entirety at a stress level of 20 percent or less of the specified minimum yield strength (SMYS) of the line pipe.
LPG Operator, Small – An operator of a liquefied petroleum gas (LPG) distribution pipeline that serves fewer than 100 customers from a single source.
m3 – A volumetric unit which is one cubic metre, 6.2898 barrels, 35.3147 ft.3, or 264.1720 U.S. gallons, each volume being considered as equal to the other.
Main, Gas – A distribution line that serves as a common source of supply for more than one service line.
Major River – A river that, because of its velocity and vessel traffic, would require a more rapid response in case of a worst case discharge. For a list of rivers see “Rolling Rivers, An Encyclopedia of America’s Rivers,” Richard A. Bartlett, Editor, McGraw-Hill Book Company, 1984.
Maximum Actual Operating Pressure – The maximum pressure that occurs during normal operations over a period of 1 year.
Maximum Allowable Operating Pressure (MAOP) – The maximum internal pressure permitted to the operation of a pipeline as defined by the Code of Federal Regulations.
Maximum Allowable Working Pressure – The maximum gage pressure permissible at the top of the equipment, containers or pressure vessels while operating at design temperature. Typically refers to LNG.
Maximum Extent Practicable – The limits of available technology and the practical and technical limits on a pipeline operator in planning the response resources required to provide the on-water recovery capability and the shoreline protection and cleanup capability to conduct response activities for a worst case discharge from a pipeline in adverse weather.
Maximum Operating Pressure (MOP) – The maximum internal pressure expected during the operation of a pipeline. MOP normally cannot exceed the maximum allowable operating pressure.
Mechanical Fitting – A mechanical device used to connect sections of pipe. The term applies only to: (1) Stab Type fittings; (2) Nut Follower Type fittings; (3) Bolted Type fittings; or (4) Other Compression Type fittings.
Natural Gas – Natural gas comes from both “conventional” (easier to produce) and “unconventional” (deeper, more difficult to produce) geological formations. The key difference between conventional and unconventional natural gas is the manner, ease and cost associated with extracting the resource.
Navigable Waters – The waters of the United States, including the territorial sea and such waters as lakes, rivers, streams; waters which are used for recreation; and waters from which fish or shellfish are taken and sold in interstate or foreign commerce.
New and Novel Technologies – Any products, designs, materials, testing, construction, inspection, or operational procedures that are not addressed in 49 CFR Parts 192, 193, or 195, due to technology or design advances and innovation for new construction. Technologies that are addressed in consensus standards that are incorporated by reference into 49 CFR Parts 192, 193, and 195 are not “new or novel technologies.”
Natural Gas Measurements – Natural gas can be measured in a number of different ways. As a gas, it can be measured by the volume it takes up at normal temperatures and pressures, commonly expressed in cubic feet. Production and distribution companies commonly measure natural gas in thousands of cubic feet (Mcf), millions of cubic feet (MMcf), or trillions of cubic feet (Tcf). While measuring by volume is useful, natural gas can also be measured as a source of energy. Like other forms of energy, natural gas is commonly measured and expressed in British thermal units (Btu). One Btu is the amount of natural gas that will produce enough energy to heat one pound of water by one degree at normal pressure. To give an idea, one cubic foot of natural gas contains about 1,027 Btus. When natural gas is delivered to a residence, it is measured by the gas utility in ‘therms’ for billing purposes. A therm is equivalent to 100,000 Btu, or just over 97 cubic feet, of natural gas.
Nominal Wall Thickness – The pipeline wall thickness listed in the pipe specifications.
Normal Operation – Functioning within ranges of pressure, temperature, flow, or other operating criteria as specified in Title 49.
Offshore – Beyond the line of ordinary low water along that portion of the coast of the United States that is in direct contact with the open seas and beyond the line marking the seaward limit of inland waters.
Oil – Oil of any kind or in any form, including, but not limited to, petroleum, fuel oil, vegetable oil, animal oil, sludge, oil refuse, oil mixed with wastes other than dredged spoil. Does not include hazardous substances under 40 CFR part 116.
On-Scene Coordinator (OSC) – The federal official designated by the Administrator of the U.S. EPA or by the Commandant of the U.S. Coast Guard to coordinate and direct federal response under subpart D of the National Contingency Plan (NCP) (40 CFR part 300).
One-Call – A notification system through which a person can notify pipeline operators of planned excavation to facilitate the locating and marking of any pipelines in the excavation area.
One-Call Notification System – A communication system and a one-call damage prevention program of a State in which an operational center receives notices from excavators of intended excavation activities and transmits the notices to operators of underground pipeline facilities and other underground facilities that participate in the system.
Onshore Oil Pipeline Facilities – New and existing pipe, rights-of-way and any equipment, facility, or building used in the transportation of oil located in, on, or under, any land within the United States other than submerged land.
Operator – A person who owns or operates an LNG facility, onshore or offshore oil pipeline facilities, onshore or offshore gas pipeline facilities, or a person who engages in the transportation of gas .
Outer Continental Shelf – All submerged lands lying seaward and outside the area of lands beneath navigable waters as defined in Section 2 of the Submerged Lands Act (43 U.S.C. 1301) and of which the subsoil and seabed appertain to the United States and are subject to its jurisdiction and control.
Outside Force Damage – Damage to a pipeline caused by earth movement, floods, unstable suspension bridge, and other circumstances not caused by excavation.
Permanent ROW – Permanent right-of-ways remain as long as the pipeline remains active and are maintained as “clear zones” therefore trees, temporary and/or permanent structures are prohibited.
Permanently Closed – Any container or facility for which: (1) All liquid and sludge has been removed from each container and connecting line; and (2) All connecting lines and piping have been disconnected from the container and blanked off, all valves (except for ventilation valves) have been closed and locked, and conspicuous signs have been posted on each container stating that it is a permanently closed container and noting the date of closure. (40 CFR 112)
Person – Term used by U.S. government and Department of Transportation per Title 49. Any individual, firm, joint venture, partnership, corporation, association, state, municipality, cooperative association, or joint stock association and includes any trustee, receiver, assignee, or personal representative thereof.
Petroleum – Crude oil, condensate, natural gasoline, natural gas liquids, and liquefied petroleum gas.
Petroleum Gas – Propane, propylene, butane, (normal butane or isobutanes), and butylene (including isomers), or mixtures composed predominantly of these gases, having a vapor pressure not exceeding 208 psi (1434 kPa) gage at 100 degrees F (38 degrees C).
Petroleum Product – Flammable, toxic, or corrosive products obtained from distilling and processing of crude oil, unfinished oils, natural gas liquids, blend stocks and other miscellaneous hydrocarbon compounds.
Pig – Generic term for a tool or vehicle that moves through the interior of the pipeline for purposes of inspecting, dimensioning, or cleaning.
Pipe, Gas – Any pipe or tubing used in the transportation of gas, including pipe-type holders.
Pipe or Line Pipe, Hazardous Liquid – A tube, usually cylindrical, through which a hazardous liquid or carbon dioxide flows from one point to another.
Pipeline – The portion of the pipeline system between the compressor stations including the pipe, protective coatings, cathodic protection system, field connections, valves and other appurtenances attached or connected to the pipe.
Pipeline, Gas – All parts of those physical facilities through which gas moves in transportation, including pipe, valves, and other appurtenance attached to pipe, compressor units, metering stations, regulator stations, delivery stations, holders, and fabricated assemblies. Per 49 CFR 192
Pipeline, Oil – All parts of an onshore pipeline facility through which oil moves including, but not limited to, line pipe, valves, and other appurtenances connected to line pipe, pumping units, fabricated assemblies associated with pumping units, metering and delivery stations and fabricated assemblies therein, and breakout tanks. Per 49 CFR 194
Pipeline Environment – Includes soil resistivity (high or low), soil moisture (wet or dry), soil contaminants that may promote corrosive activity, and other known conditions that could affect the probability of active corrosion.
Pipeline Facility – New and existing piping, 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.
Pipeline Infrastructure – Includes all parts of the physical facilities used to transport fluid, gas, hazardous liquid, or carbon dioxide.
Pipeline ROW Easement – Consecutive private property easements acquired by, or granted to, the pipeline company to construct and maintain pipelines on consecutive private property easements to transport hazardous liquid and natural gas from source to consumer.
Pipeline System – All portions of the physical facilities through which gas moves during transportation including pipe, valves, and other appurtenances attached to the pipe, such as compressor units, metering stations, regulator stations, delivery stations, holders and other fabricated assemblies. (See 49 CFR 192)
Piping – Pipe, tubing, hoses, fittings, valves, pumps, connections, safety devices or related components for containing the flow of hazardous fluids. Typically used in referring to LNG.
Potential Impact Circle – Is a circle of radius equal to the potential impact radius (PIR).
Potential Impact Radius (PIR) – PIR means the radius of a circle within which the potential failure of a pipeline could have significant impact on people or property. PIR is determined by the formula r = 0.69 (square root of (p*d2)), where ‘r’ is the radius of a circular area in feet surrounding the point of failure, ‘p’ is the maximum allowable operating pressure (MAOP) in the pipeline segment in pounds per square inch and ‘d’ is the nominal diameter of the pipe- line in inches. r = 0.69 is the factor for natural gas. This number will vary for other gases depending upon their heat of combustion. An operator transporting gas other than natural gas must use section 3.2 of ASME/ANSI B31.8S (incorporated by reference, see 49 CFR 192.7) to calculate the impact radius formula.
Produced Water Container – A storage container at an oil production facility used to store the produced water after initial oil/water separation, and prior to reinjection, beneficial reuse, discharge, or transfer for disposal.
Production Facility – Piping or equipment used in the production, extraction, recovery, lifting, stabilization, separation or treating of petroleum or carbon dioxide, or associated storage or measurement. (To be a production facility under this definition, piping or equipment must be used in the process of extracting petroleum or carbon dioxide from the ground or from facilities where CO2 is produced, and preparing it for transportation by pipeline. This includes piping between treatment plants which extract carbon dioxide, and facilities utilized for the injection of carbon dioxide for recovery operations.) Per 49 CFR 195.
Remediation – A repair or mitigation activity an operator takes on a covered segment to limit or reduce the probability of an undesired event occurring or the expected consequences from the event.
Response Activities – The containment and removal of oil from the water and shorelines, the temporary storage and disposal of recovered oil, or the taking of other actions as necessary to minimize or mitigate damage to the environment.
Response Plan – The operator’s core plan and the response zone appendices for responding, to the maximum extent practicable, to a worse case discharge of oil, or the substantial threat of such a discharge.
Response Zone – A geographic area either along a length of pipeline or including multiple pipelines, containing one or more adjacent line sections, for which the operator must plan for the deployment of, and provide, spill response capabilities. The size of the zone is determined by the operator after considering available capability, resources, and geographic characteristics.
Rupture – The process or instance of breaking open or bursting of a pipe; or, The propagation or growth of a defect to such an extent that a pipe becomes completely unserviceable.
Rural Area – Outside the limits of any incorporated or unincorporated city, town, village, or any other designated residential or commercial area such as a subdivision, a business or shopping center, or community development.
Service Line – A distribution line that transports gas from a common source of supply to an individual customer, to two adjacent or adjoining residential or small commercial customers, or to multiple residential or small commercial customers served through a meter header or manifold. A service line ends at the outlet of the customer meter or at the connection to a customer’s piping, whichever is further downstream, or at the connection to customer piping if there is no meter.
Service Regulator – The device on a service line that controls the pressure of gas delivered from a higher pressure to the pressure provided to the customer. A service regulator may serve one customer or multiple customers through a meter header or manifold.
Smart Pig – Device or vehicle that inspects the wall of a pipe also known as an in-line inspection tool.
Specified Minimum Yield Strength (SMYS) – The minimum yield strength, expressed in pounds per square inch, prescribed by the specification under which the material is purchased from the manufacturer. For steel pipe manufactured in accordance with a listed specification, the yield strength specified as a minimum in that specification; or, for steel pipe manufactured in accordance with an unknown or unlisted specification, the yield strength determined in accordance with 49 CR 192.107(b).
Spill Prevention, Control, and Countermeasure (SPCC) Plan – A document required by 40 CFR 112.3 that details the equipment, workforce, procedures, and steps to prevent, control, and provide adequate countermeasures to an oil discharge.
Stress Level – The level of tangential or hoop stress, usually expressed as a percentage of specified minimum yield strength (SMYS).
Storage Tank – A container for storing a hazardous fluid.
Supervisory Control and Data Acquisition (SCADA) System – A computer-based system or systems used by a controller in a control room that collects and displays information about a pipeline facility and may have the ability to send commands back to the pipeline facility.
Surge Pressure – Pressure produced by a change in velocity of the moving stream that results from shutting down a pump station or pumping unit, closure of a valve, or any other blockage of the moving stream.
Survey (Verb) – The examination, measurement, inspection and recording of the area and features of an area of land intended be used to construct a map, plan, or survey. A survey may be used to investigate the options of a proposed pipeline preferred route.
Survey (Noun) – A map, plan, or detailing the results of the conducted survey.
Temporary ROW – The temporary ROW is outside the boundaries of the Permanent ROW. Typically needed for working space during construction, the size and longevity of the temporary easement vary depending on the pipeline system needs. Average Temporary ROW requests are 50 feet wide, may be wider or narrower, and grant removal of trees, earth and all obstructions to pipeline construction.
Toxic Product or Poisonous Material – A material, other than a gas, which is known to be so toxic to humans as to afford a hazard to health during transportation, or which, in the absence of adequate data on human toxicity: (1) Is presumed to be toxic to humans because it falls within any one of the following categories when tested on laboratory animals (whenever possible, animal test data that has been reported in the chemical literature should be used): (i) Oral Toxicity. A liquid or solid with an LD50 for acute oral toxicity of not more than 300 mg/kg, (ii) Dermal Toxicity. A material with an LD50 for acute dermal toxicity of not more than 1000 mg/kg, (iii) Inhalation Toxicity. (A) A dust or mist with an LC50 for acute toxicity on inhalation of not more than 4 mg/L. Per 49 CFR 173.132 Class 6, Division 6.1-Definitions.
Transfer Piping or Transfer System – A system of permanent and temporary piping used for transferring hazardous fluids between any of the following: Liquefaction process facilities, storage tanks, vaporizers, compressors, cargo transfer systems, and facilities other than pipeline facilities. Typically used in reference to LNG.
Transmission Line – A pipeline, other than a gathering or distribution line, that (1) transports gas from a gathering line or storage facility to a distribution center, storage facility, or large volume customer that is not down-stream from a distribution center; (2) operates at a hoop stress of 20 percent or more of SMYS; or (3) transports gas within a storage field.
Transportation of Gas – The gathering, transmission, or distribution of gas by pipeline or the storage of gas, in or affecting interstate or foreign commerce.
Underground Natural Gas Storage Facility – A facility that stores natural gas in an underground facility incident to natural gas transportation, including: (1) A depleted hydrocarbon reservoir; (2) An aquifer reservoir; or (3) A solution-mined salt cavern reservoir, including associated material and equipment used for injection, withdrawal, monitoring, or observation wells, and wellhead equipment, piping, rights-of-way, property, buildings, compressor units, separators, metering equipment, and regulator equipment.
Unusually Sensitive Area (USA) (also see USA Drinking Water Resource and USA Ecological Resource) – A drinking water or ecological resource area that is unusually sensitive to environmental damage from a hazardous liquid pipeline release. Per 49 CFR 195.6.
USA Drinking Water Resource – A drinking water resource area that is unusually sensitive to environmental damage from a hazardous liquid pipeline release, including: (1) The water intake for a Community Water System (CWS) or a Non-transient Non-community Water System (NTNCWS) that obtains its water supply primarily from a surface water source and does not have an adequate alternative drinking water source; (2) The Source Water Protection Area (SWPA) for a CWS or a NTNCWS that obtains its water supply from a Class I or Class IIA aquifer and does not have an adequate alternative drinking water source. Where a state has not yet identified the SWPA, the Wellhead Protection Area (WHPA) will be used until the state has identified the SWPA; or (3) The sole source aquifer recharge area where the sole source aquifer is a karst aquifer in nature.
USA Ecological Resource – An ecological resource area that is unusually sensitive to environmental damage from a hazardous liquid pipeline release, including: (1) An area containing a critically imperiled species or ecological community; (2) A multi-species assemblage area; (3) A migratory waterbird concentration area; (4) An area containing an imperiled species, threatened or endangered species, depleted marine mammal species, or an imperiled ecological community where the species or community is aquatic, aquatic dependent, or terrestrial with a limited range; or (5) An area containing an imperiled species, threatened or endangered species, depleted marine mammal species, or imperiled ecological community where the species or community occurrence is considered to be one of the most viable, highest quality, or in the best condition, as identified by an element occurrence ranking (EORANK) of A (excellent quality) or B (good quality).
Vaporization – An addition of thermal energy changing a liquid to a vapor or gaseous state. Typically refers to LNG.
Vaporizer – A heat transfer facility designed to introduce thermal energy in a controlled manner for changing a liquid to a vapor or gaseous state. Typically refers to LNG.
Waterfront LNG Plant – An LNG plant with docks, wharves, piers, or other structures in, on, or immediately adjacent to the navigable waters of the United States or Puerto Rico and any shore area immediately adjacent to those waters to which vessels may be secured and at which LNG cargo operations may be conducted.
Weak Link – A device or method used when pulling polyethylene pipe, typically through methods such as horizontal directional drilling, to ensure that damage will not occur to the pipeline by exceeding the maximum tensile stresses allowed.
Welder – A person who performs manual or semi-automatic welding.
Welding Operator – A person who operates machine or automatic welding equipment.
Worst Case Discharge – The largest foreseeable discharge of oil, including a discharge from fire or explosion, in adverse weather conditions. This volume will be determined by each pipeline operator for each response zone and is calculated according to 49 CFR 194.105.