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Amperage, amps - A measurement of the amount of electric current.<

Appliance - A device used in the home to perform domestic chores, such as a clothes dryer, dishwasher, refrigerator, toaster, etc.

Atom - The smallest unit of matter. Scientists so far have found 112 different kinds of atoms. Everything in the world is made of different combinations of these atoms.

Automatic Meter Reading (AMR) - "Real time" monitoring of natural gas quantities and characteristics as it passes through a specific location.

Average Therm Per Day - Therm usage for the billing period divided by the days of service for the same billing period.


Back Pressure - Pressure against which a fluid is flowing. May be composed of friction in pipes, restrictions in pipes, valves, pressure in vessels to which fluid is flowing, hydrostatic head, or other resistance to fluid flow.

Back Fill - Earth or other material which has been used to refill a ditch or trench. Also, the act of refilling a ditch or trench.

Bell Hole - A hole dug to allow room for workmen to make a repair or connection in buried pipe, such as caulking bell-and-spigot pipe or welding steel pipe. In the broad sense, any hole other than a continuous trench opened for working on a buried facility.

Billing Cycle - The regular, periodic interval used by a utility for reading the meters of customers for billing purposes.

Biogas - Biogas is a mixture of methane and carbon dioxide that is generated when bacteria degrade biological material in the absence of oxygen, in a process known as anaerobic digestion. Biogas can be burned in boilers to produce hot water and steam and to generate electricity. It can also be used as a vehicle fuel.

Biomass - Organic materials, such as wood by products and agricultural wastes, that can be burned to produce energy or converted into a gas and used for fuel.

Boiler Efficiency - The ratio of the useful heat output to the heat input, multiplied by 100 and expressed in percent.

Booster - A compressor used to raise pressure in a gas or oil pipeline.

Booster Station - A facility containing equipment which increases pressure on oil or gas in a pipeline.

Btu per Cubic Foot - A measure of the heat available or released when one cubic foot of gas is burned.

Burner Tip - An attachment for a burner head which forms a burner port modified for a specific application. Also, a generic term that refers to the ultimate point of consumption for natural gas.

Butane - A hydrocarbon gas that is one of the ingredients in natural gas. Butane molecules consist of four carbon atoms and ten hydrogen atoms.


Cap Rock - The cap rock keeps underground natural gas deposits from escaping upward. Granite is a common cap rock.

Carbon Dioxide - A colorless, odorless, nonpoisonous gas that is a normal part of the air we breathe. Carbon dioxide is exhaled by humans and animals, and is absorbed by green growing things and by the sea. Carbon dioxide molecules consist of one carbon atom and two oxygen atoms. A small amount of carbon dioxide is found in natural gas.

Carbon Monoxide - A colorless, odorless, poisonous gas that is formed when fuel is burned without enough oxygen. Carbon monoxide alarms can be installed in the home to alert people to its presence. Carbon monoxide molecules consist of one carbon atom and one oxygen atom.

Cathodic Protection - A technique to prevent the corrosion of a metal surface by making that surface the cathode of an electrochemical cell.

Check Meter - A device for measuring utility service consumption within individual dwelling units where the utility service is supplied through a master meter.

Chill Factor - The temperature (at zero wind velocity) which would produce the same chilling effect as a particular combination of temperature and wind velocity.

City Gate (Town Border Station) - See GATE STATION.

Circuit - A circular path in which electricity travels.

Coal - A fuel consisting of black or brown rock that is taken out of the ground at large mines.

Combustible - Capable of burning.

Combustion - The process of burning.

Common Trench - A trench containing two or more utilities.

Compressed Natural Gas (CNG) - Natural gas in high-pressure surface containers that is highly compressed (though not to the point of liquefaction). CNG is used extensively as a transportation fuel for automobiles, trucks, and buses in some parts of Italy, New Zealand, and in Western Canada, and has recently begun to penetrate some regions of the United States. Small amounts of natural gas are also transported overland in high-pressure containers.

Compression - The action on a material which decreases its volume as the pressure to which it is subjected increases.

Compressor Station - Any permanent combination of facilities which supplies the energy to move gas at increased pressure from fields, in transmission lines, or into storage.

Compressor Stations - Locations along the interstate pipeline at which large (thousands of horsepower) natural gas-powered engines increase the pressure of the market natural gas stream flowing through the station by compression.

Conductor - Something that allows electricity to flow through it easily. Water and most metals are good conductors. Conductors can allow electricity to flow through them because the electrons in their atoms move between atoms very easily.

Cost Per Therm - Total charges for delivery and supply for the service divided by your total therm usage

Cubic Foot (cf) - The most common unit of measurement of natural gas volume. It takes eight gallons of liquid to equal one cubic foot. One hundred cubic feet equals one therm.

Cubic Meter - A common unit of measurement of natural gas volume. It takes 1,000 liters of liquid to equal one cubic meter.

Current - The movement or flow of electricity.


Damper - A movable plate for regulating the draft in a chimney.

Degree Day, Cooling - A measure of the need for air conditioning (cooling) based on temperature and humidity. Although cooling degree days are published for many weather stations, a specific procedure has not been generally accepted.

Degree Day, Heating - A measure of the coldness of the weather experienced, based on the extent to which the daily mean temperature falls below a reference temperature, usually 65 degrees F.

Dekatherm - A unit of heating value equivalent to 10 therms or 1,000,000 Btus. Here are some frequently used units for measuring natural gas.

  • 1 cubic foot (cf) = 1,027 Btu
  • 100 cubic feet (1 ccf) = 1 therm (approximate)
  • 1,000 cubic feet (1 Mcf) = 1,027,000 Btu (1 MMBtu)
  • 1,000 cubic feet (1 Mcf) = 1 dekatherm (10 therms)
  • 1 million (1,000,000) cubic feet (1 Mmcf) = 1,027,000,000 Btu
  • 1 billion (1,000,000,000 cubic feet (1 bcf) = 1.027 trillion Btu
  • 1 trillion (1,000,000,000,000) cubic feet (1Tcf) = 1.027 quadrillion Btu

To put this in context,

  • One-thousand cubic feet of natural gas is approximately enough to meet the natural gas needs of an average home (space-heating, water-heating, cooking, etc.) for four days.
  • In 2004, the average American home consumed 77,900 cubic feet of natural gas (or 77.9 million Btu). On a daily basis, the average U.S. home used 213 cubic feet of natural gas. (Source: American Gas Association Gas Facts 2006 with 2004 data)
  • Most natural gas household bills display the amount of natural gas consumed by the 'therm' (100,000 Btu) or in hundreds of cubic feet (100 cubic feet - 1 Ccf).
  • Looking at larger quantities, 1 billion cubic feet (Bcf) of natural gas is enough to meet the needs of approximately 10,000 - 11,000 American homes for one year.
  • Five-trillion cubic feet of natural gas is enough to meet the needs of 5 million households for 15 years.

Demand Meters - A device which indicates or records the instantaneous, maximum, or integrated (over a specified period) demand.

Dig-In - When buried gas facilities are damaged by excavators.

Distribution Main - Underground pipelines that carry natural gas from utilities to homes and businesses.

Distribution. System – Natural Gas - Generally mains, services, and equipment which carry or control the supply of gas from the point of local supply to and including the sales meters. The system operates at various pressures as indicated below.

  • High Pressure: A system which operates at a pressure higher than the standard service pressure delivered to the customer; thus, a pressure regulator is required on each service to control pressure delivered to the customer. Sometimes this is referred to as medium pressure.
  • Low Pressure or Utilization Pressure: A system in which the gas pressure in the mains and service lines is substantially the same as that delivered to the customers' appliances; ordinarily a pressure regulator is not required on individual service lines.

Distribution Wires - Power lines that carry electricity through towns and neighborhoods to homes and businesses. Distribution lines can run overhead or underground.


Ethane - A hydrocarbon gas that is one of the ingredients in natural gas. Ethane molecules each contain two carbon atoms and six hydrogen atoms.

Electricity - The flow of electrons.

Electron - The basic particle that orbits the nucleus of an atom. The flow of electrons produces electricity.

Energy - The ability to do work. People get energy from food. Your toaster and your washing machine get their energy from electricity.

Extracted - Taken out. Natural gas is extracted from the earth through deep wells.


Federal Energy Regulatory Commission (FERC) - An agency of the government of the United States created by an Act of Congress, the Department of Energy Organization Act, in 1977. This Act transferred to the FERC most of the former Federal Power Commission's interstate regulatory functions over the electric power and natural gas industries. The Act also transferred from the Interstate Commerce Commission the authority to set oil pipeline transportation rates and to set the value of oil pipelines for rate making purposes. In 1978, Congress passed the Natural Energy Act, broadening the FERC's jurisdiction and regulatory functions. The FERC now also regulates producer sales of natural gas in intrastate commerce. The FERC establishes uniform ceiling prices for each of several categories of natural gas, and these prices apply to all sales on a nationwide basis.

Feeder (Main) - A gas main or supply line that delivers gas from a city gate station or other source of supply to the distribution networks.

Flue - A flue is a pipe that carries the products of combustion out of a building. Fireplaces have flues that direct the smoke from a fire up the chimney. Natural gas appliances and equipment have flue pipes that vent to the outdoors.

Fluorescent Bulb - A light bulb that emits light because the gas inside it glows when it is charged by electricity.

Fossil Fuels - Coal, oil, and natural gas are known as fossil fuels because they were formed from the fossilized remains of animals or plants that lived long ago.

Fuel - A substance that can be used to produce heat.

Fuel Cell - A technology that produces electricity through a chemical reaction similar to that found in a battery.


Gas - A substance whose molecules are randomly moving so quickly that the molecules easily separate from one another. Gases will spread out and take on the shape and volume of whatever they are in --a jar, a room, or the atmosphere.

Gas Bill - A statement received monthly from a natural gas utility showing how much natural gas your household used and how much you will need to pay for it.

Gas Lines - Small pipes (1 to ¾ inch in diameter) that carry natural gas to home appliances.

Gas Meter - A device that records how much natural gas is being used in a building.

Gate Station - Generally a location at which gas changes ownership, from one party to another, neither of which is the ultimate consumer. It should be noted, however, that the gas may change from one system to another at this point without changing ownership. Also referred to as city gate station, town border station, or delivery point.

Generator - A machine that converts mechanical energy into electrical energy.

Geothermal Energy - Energy that is generated by converting hot water or steam from deep beneath the Earth's surface into electricity.

GFCI (ground fault circuit interrupter) - GFCIs are safety devices found on appliance cords and power outlets. If a GFCI detects electricity leaving a circuit, it quickly shuts off the electricity to prevent serious shock.


Hydrocarbon - A compound that contains only hydrogen and carbon atoms. Natural gas is a mixture of hydrocarbons.

Hydroelectricity - Electricity that is generated when falling water makes a turbine spin.

Hydrogen - A colorless, odorless gas that is the simplest and most common element in the universe.


Ignition - The process of lighting a fire or causing a fuel to start burning.

Insulator - Something that does not allow electricity to flow through it easily. Glass and special rubber are good insulators. Insulators do not allow electricity to flow through them easily because the electrons in their atoms do not move easily from atom to atom.

Incandescent Bulb - A light bulb that emits light due to the glowing of a heated filament inside it.


Kilowatt - 1,000 watts of electricity.

Kilowatt–Hour - One kilowatt of electricity produced or used in one hour.


Landfills - Places for trash and garbage disposal where the waste is buried between layers of earth.

Liquid - A substance whose molecules are in constant, random motion but do not move as fast as those in a gas. A liquid can take on the shape of its container but keeps the same volume, no matter what container it's in.


Megawatt - 1,000,000 watts of power or 1,000 kilowatts.

Mercaptan - A chemical added to natural gas that makes it smell like rotten eggs so people will know if natural gas is leaking.

Methane - A hydrocarbon gas that is the main ingredient in natural gas. Methane molecules each contain one carbon atom and four hydrogen atoms.

Molecule - The smallest part of a substance that has all of the chemical properties of that substance.


Natural Gas - A hydrocarbon gas found in the earth, composed of methane, ethane, butane, propane, nitrogen, carbon dioxide, hexane, heptanes, and pentane.

Nonrenewable Resource - A resource that is limited. Fossil fuels (oil, coal, and natural gas) are considered nonrenewable resources because once they are used up we cannot create more of them.

Nucleus - The center of an atom. The nucleus contains tiny particles called protons and neutrons. Orbiting around the nucleus are electrons.


Odorant - Any material added to natural or LP gas in small concentrations to impart a distinctive odor. Odorants in common use include various mercaptans, organic sulfides, and blends of these. Compare MERCAPTANS.

Oil - A fossil fuel in liquid form that is obtained through wells drilled deep in the earth.

One Call Service - The utility locater service that should be called before digging into the ground. This service marks the location of buried utilities so people can work a safe distance away from them.

Operator - An entity which manages and controls a facility and the gas moving through that facility. The operator performs the day-to-day operations, contract scheduling, communications, and routinely monitors, tests, and repairs facilities and/or measurement equipment. The operator is not necessarily the owner. A producer operator operates a well. A transportation operator operates a gathering system, pipeline or local distribution company. A plant operator operates a processing or extraction plant. A consumer operator operates an end-user facility.


Photovoltaic Cell - A device that changes sunlight directly into electricity.

Pilot Light - A small flame or spark used to ignite gas at a burner. Most newer appliances have electric pilots; older appliances have a small permanent flame.

Power Plant - A place where electricity is generated.

Power Line - A wire used to carry electricity. Power lines are located overhead or buried underground.

Processing Plant - A place where natural gas is treated to remove impurities.

Proton - A basic particle in an atom's nucleus that has a positive electrical charge.

Propane - A hydrocarbon gas that is one of the ingredients in natural gas. Propane molecules each contain three carbon atoms and eight hydrogen atoms.


R-Value - A measure of thermal resistance of a material, equal to the reciprocal of the U-Value. The R-Value is expressed in terms of degrees Fahrenheit times hours, times square feet per Btu.

Regulator, Domestic Appliance Pressure - A device either adjustable or non-adjustable for controlling and maintaining a uniform outlet gas pressure.

  • Spring Type, Adjustable:  A regulator in which the regulating force acting upon the diaphragm is derived principally from a spring, the loading of which is adjustable.
  • Spring Type, Nonadjustable:  A regulator in which the regulating force acting upon the diaphragm is derived principally from a spring, the loading of which is not adjustable.

Either of the above types may be further classified as follows.

  • Main Burner Load Application: A regulator capable of controlling the flow of gas to main burners only. In such applications, the pilot is taken off upstream from the regulator.
  • Main Burner and Pilot Load Application: A regulator capable of controlling the flow of gas to main and pilot burners. In such applications the pilot is taken off downstream from the regulator valve.

Regulator, Monitoring - A pressure regulator set in series with a control pressure regulator for the purpose of automatically taking over, in an emergency, the control of the pressure downstream of the station in case that pressure tends to exceed a set maximum.

Reservoir Rock - A layer of porous sedimentary rock, usually sandstone or limestone. The natural gas migrates into the pores of the reservoir rock.


Service Line - A pipeline that carries natural gas from a distribution main up to the gas meter at a building.

Solar Cells - Solar cells collect sunlight and convert it into electricity.

Solar Energy - Energy from the sun.

Storage Tanks - Large aboveground or underground tanks used to store natural gas for future use.

Substation - A facility where transformers reduce or boost electricity's voltage.

System Storage - Storage Facilities – pipelines or man-made or natural underground caverns used by the pipeline to store gas for its own use, to meet the peak day requirements of its sales customers, and to provide flexibility on its system.


Therm - A unit of measurement used to determine how much natural gas or propane you used for a month. Your gas meter measures in cubic feet. We use a multiplier to convert cubic feet into therms. The multiplier varies depending on the altitude of where you live as well as the heat content of the gas that we provide. 

Therm Factor - Determined by the utility and based on the energy content of the natural gas, which can vary by supplier. Some utilities use an average therm factor.

Thermostat - A device that controls the temperature of a heating or cooling system.

Transformer - A device used to increase or decrease electricity's voltage and current.

Transmission - The system in an automobile that transfers energy from the engine or motor to the wheels, causing the wheels to turn.

Transmission Lines - Power lines that carry high voltage electricity long distances.

Transmission Pipes - A network of large steel pipes that carries natural gas from processing plants to utilities.

Transmission System – Natural Gas - Pipelines (mains) installed for the purpose of transmitting gas from a source or sources of supply to one or more distribution centers, to one or more large volume customers, or a pipeline installed to interconnect sources of supply. In typical cases, transmission lines differ from gas mains in that they operate at higher pressures, are longer, and the distance between connections is greater.

Turbine - A device used in the generation of electricity. It has a shaft with blades at one end and electromagnets at the other. Water or steam or some other energy source pushes the blades, which make the shaft and the magnets spin very fast. The magnet end is surrounded by heavy coils of copper wire, and the spinning magnets cause electrons in the wire to begin to move, creating electricity.


Utility - A supplier that provides a basic service such as delivering electricity, natural gas, and/or water to a community.


Valve - A movable part that controls the flow of a liquid or gas through a pipe or other channel.

Voltage, Volts - A measure of the pressure under which electricity flows.

Volume - The amount of space taken up by something.


Wattage, Watts - A measure of the amount of work done by a certain amount or amperage of electric current at a certain pressure or voltage.

Well - A hole drilled or bored into the earth to bring up water, sulfur, natural gas, or petroleum.

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