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Glossary of Terms


637 S Registrant: enterer, position holder, refiner, terminal operator, or throughputter of gasoline, diesel fuel, or kerosene, or industrial user of gasoline

(IRS Form 637 – Application for Registration [For Certain Excise Tax Activities]


Additives: Methyl alcohol, ethyl alcohol (ethanol), tertiary butyl alcohol (TBA), isopropyl alcohol, normal butyl alcohol, isobutyl alcohol, methyl tertiary butyl ether (MTBE), tertiary amyl methyl ether (TAME), di-isopropyl ether.

Aviation Gasoline (Finished): A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in aviation reciprocating engines. Fuel specifications are provided in ASTM Specification D 910 and Military Specification MIL-G-5572.

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Barrel: A volumetric unit of measure for crude oil and petroleum products equivalent to 42 U.S. gallons.

Biodiesel: A petroleum diesel fuel substitute that is manufactured from vegetable oils, animal fats, or recycled greases combined with alcohol (ethanol or methanol) in the transeterification process.

Blending: Mixing of two compatible fuels having different properties in order to produce an intermediate fuel.

Blendstock: most frequently applied to motor gasoline ingredients, a component combined with other materials at a refinery to produce a finished petroleum product.

Blendstocks: Any petroleum product component of gasoline: straight-run gasoline, raformate, alkylates, butane, pentane, hexane, hydrocrackate, toluene, straight-run naphtha, catalytically cracked gasoline, thermally cracked gasoline, coker gasoline, polymer gasoline, natural gasoline, pentane mixture, raffinates, isomerate, butenes, aviation gasoline.

Bulk: Any quantity of fuel sold or delivered except into fuel supply tanks of vehicles.

Bulk Distribution System/Bulk Transfer System/Bulk Terminal System: the motor fuel distribution system consisting of refineries, pipelines, vessels (e.g., boats and barges), and terminals; and not including ground transportation such as tank cars, rail cars, trailers, and trucks.

Bulk Facility: A facility that receives gasoline and/or diesel fuel by pipeline, rail, or barge and then delivers the fuel into a cargo tank or barge. The term does not include petroleum products consumed at an electric generating facility.

Bulk Plant: The facilities of a distributor or supplier which has the storage capacity to receive and disburse fuel in bulk.

Bulk Sales: Wholesale sales of gasoline in individual transactions which exceed the size of a truckload.

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Cargo Tanks: An assembly used for transporting, hauling or delivering liquids, comprising a tank, which may be one compartment or may be subdivided into two or more compartments mounted on a wagon, automobile, truck, trailer or wheels, together with its accessory piping, valves and meters, excluding fuel supply tanks connected to the carburetor or fuel injector of a motor vehicle.

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Daisy Chain: A term applied to a series of transactions in which fuel is transferred between several parties, often related. Usually used (legally) to overcome state and federal regulations. Sometimes used illegally to hide identity of purchaser, or to disguise illegal transactions.

Dealer: A person who is the operator of a service station or other retail outlet who delivers motor fuel into the fuel supply tanks of motor vehicles or motorboats.

Distillate Fuel Oil: A general classification for one of the petroleum fractions produced in conventional distillation operations. Products known as No. 1, No.2, and No. 4 diesel fuel are used in on-highway diesel engines, such as those in railroad locomotives and agricultural machinery. Products known as No. 1, No. 2, and No. 4 fuel oils are used primarily for space heating and electric power generation.

Distributor: A person who regularly makes sales or distributions of gasoline which are not deliveries into the fuel supply tanks of motor vehicles, motorboats, or aircraft, or who refines, distills, manufactures, produces, or blends for sale or distribution tax-free gasoline in this state, imports or exports tax-free gasoline other than in the fuel supply tanks of motor vehicles, or in any other manner acquires or possesses tax-free gasoline.

Draft: the distance between a water vessel’s keel and the waterline.

Dyed Diesel: Diesel fuel to which color has been added to indicate that is not suitable for use in vehicles that are driven on highways and public roads.

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Electronic Data Interchange (EDI): The computer-to-computer exchange of structured information, by agreed message standards, from one computer application to another by electronic means and with a minimum of human intervention.

Electronic Funds Transfer (EFT): An electronic method used to remit funds directly from a bank account.

Ethanol: Ethanol can be produced chemically from ethylene or biologically from the fermentation of various sugars from carbohydrates found in agricultural crops and cellulosic residues from crops or wood.

Excise Tax: A tax on the sale or use of specific products or transactions.

ExSTARS: a subsystem/subcomponent of ExFIRS (Excise Files Information Retrieval System) designed to provide an automated means to gather and analyze motor fuel industry records and determine which activities are not remitting correct federal and state motor fuel excise taxes; ExSTARS tracks and processes terminal distribution data including fuels volume movement activity, inventory balances, and destination information, as reported by terminal operators, pipeline operators, and transport carriers. This data, in conjunction with information reported on the taxpayers' Quarterly Federal Excise Return (Form 720) helps identify discrepancies between distribution amounts and taxes paid. (IRS ExSTARS Information)

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Fractionation Plant: a processing plant that separates hydrocarbon mixtures based on the vapor pressures of its component molecules, either by adding heat (distillation) or removing heat (condensation); products such as propane, butane, and ethane are produced in this process.

Fuel Oil: The heavy distillates from the oil refining process; used as fuel for power stations, marine boilers.

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Gas Plant Operator: Any firm, including a gas plant owner, which operates a gas plant and keeps the gas plant records. A gas plant is a facility in which natural gas liquids are separated from natural gas, or in which natural gas liquids are fractionated or otherwise separated into natural gas liquid products or both.

Gasohol: A blend of finished motor gasoline containing alcohol (generally ethanol but sometimes methanol) at a concentration of 10 percent or less by volume.

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International Fuel Tax Agreement (IFTA): A base state fuel tax agreement among jurisdictions to simplify the reporting of fuel taxes by interstate motor carriers. Upon application, the carrier's base jurisdiction issues credentials which allow the IFTA licensee to travel in all IFTA jurisdictions.

International Fuel Tax Association, Inc. (IFTA, Inc.): A national organization that maintains a base state fuel tax agreement among participating jurisdictions in order to simplify the reporting of fuel taxes by interstate motor carriers. Upon application, the carrier's base jurisdiction issues credentials which allow the IFTA licensee to travel in all IFTA jurisdictions. (

International Registration Plan (IRP): A U.S. based plan that allows for the distribution of registration fees for commercial motor vehicles traveling inter-jurisdictionally through member states and provinces. (

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Kerosene: A light petroleum distillate that is used in space heaters, cook stoves, and water heaters and is suitable for use as a light source when burned in wick-fed lamps. Kerosene has a maximum distillation temperature of 400 degrees Fahrenheit at the 10-percent recovery point, a final boiling point of 572 degrees Fahrenheit, and a minimum flash point of 100 degrees Fahrenheit. Included are No. 1-K and No. 2-K, the two grades of kerosene called range or stove oil, which have properties similar to those of No. 1 fuel oil.

Kerosene-Type Jet Fuel: A kerosene-based product having a maximum distillation temperature of 400 degrees Fahrenheit at the 10-percent recovery point and a final maximum boiling point of 572 degrees Fahrenheit and meeting ASTM Specification D 1655 and Military Specifications MIL-T-5624P and MIL-T-83133D (Grades JP-5 and JP-8). It is used for commercial and military turbojet and turboprop aircraft engines.

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Lightering: the process of transferring oil cargo between vessels of largely different sizes and is undertaken as many port facilities cannot accept ocean-faring tankers of the size of oil transports. (

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Mineral Spirits: also called Stoddard solvent, a petroleum distilate commonly used as a paint thinner and mild solvent for cleaning and degreasing machine tools and parts.

Motor Gasoline (Finished): A complex mixture of relatively volatile hydrocarbons with or without small quantities of additives, blended to form a fuel suitable for use in spark-ignition engines. Motor gasoline, as defined in ASTM Specification D-4814 or Federal Specification VV-G-1690B, is characterized as having a boiling range of 122 to 158 degrees Fahrenheit at the 10 percent recovery point to 365 to 374 degrees Fahrenheit at the 90 percent recovery point. "Motor Gasoline" includes conventional gasoline; all types of oxygenated gasoline, including gasohol; and reformulated gasoline, but excludes aviation gasoline.

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Naphtha: a generic term applied to a petroleum fraction with an approximate boiling range between 122 degrees Fahrenheit and 400 degrees Fahrenheit.

Naphtha-Type Jet Fuel: A fuel in the heavy naphtha boiling range with an average gravity of 52.8 degrees API, 20 to 90 percent distillation temperatures of 290 degrees to 470 degrees Fahrenheit, and meeting Military Specification MIL-T-5624L (Grade JP-4). It is used primarily for military turbojet and turboprop aircraft engines because it has a lower freeze point than other aviation fuels and meets engine requirements at high altitudes and speeds.

Natural Gasoline: (also known as casing head gas because it can be sourced at the head of an oil well) is a natural gas liquid with a vapor pressure between natural gas condensate and liquefied petroleum gas.

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Pipeline Terminal: The storage and loading facilities at pipeline outlets, usually of the major oil companies.

Position Holder: with respect to a liquid product in a terminal, the person that holds the inventory position with respect to the liquid product under a contractual agreement with the terminal operator for the use of storage facilities and terminaling services at a terminal as reflected on the records of the terminal operator; the term also includes a terminal operator that owns a liquid product in its terminal. (IRS Instructions for Forms 720-TO and 720-CS; U.S. Master Excise Tax Guide)

PTO: Power take-off equipment. Any equipment mounted on a truck which operates off of the mechanical power of the engine. Would not include hydraulic equipment powered by electricity.

Prime Supplier: A firm that produces, imports, or transports selected petroleum products across State boundaries and local marketing areas, and sells the product to local distributors, local retailers, or end users.

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Rack: A dock, a platform, or an open bay with metered pipes, hoses or both that is used for delivering motor fuel or special fuel from a refinery or terminal into the cargo area of a motor vehicle, rail car, marine vessel, or aircraft for subsequent transfer or use into the engine fuel supply tank of a locomotive or any self-propelled vehicle.

Rack Sales: Wholesale truckload sales or smaller of gasoline where title transfers at a terminal.

Raffinate: a low-octane mixture that remains after aromatics extraction from reformate; used as a motor gasoline blendstock.

Refiner: A firm or the part of a firm that refines products or blends and substantially changes products, or refines liquid hydrocarbons from oil and gas field gases, or recovers liquefied petroleum gases incident to petroleum refining and sells those products to resellers, retailers, resellers/retailers, or ultimate consumers. "Refiner" includes any owner of products which contracts to have those products refined and then sells the refined products to resellers, retailers, or ultimate consumers.

Refinery: A plant used to separate the various components present in crude oil and convert them into usable products or feedstock for other processes.

Reformate: the high octane products of a catalytic reformer used as a motor or aviation fuel blendstock that can also be processed to extract benzene, toluene and xylenes.

Reformer: a refinery’s catalytic processing unit which produces a highly aromatic stream (reformate) used primarily as high-octane blendstock.

Reseller: A firm (other than a refiner) that carries on the trade or business of purchasing refined petroleum products and reselling them to purchasers other than ultimate consumers.

Reseller/Retailer: A firm (other than a refiner) that carries on the trade or business activities of both a reseller and a retailer; i.e., purchasing refined petroleum products and reselling them to purchasers who may be either ultimate or other than ultimate consumers.

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Splash Blend: To blend or mix two or more products together by merely adding one product to the other such as alcohol to gasoline in a cargo tank compartment or even a service station underground tank.

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Tax Avoidance: An action taken to lessen tax liability and maximize after-tax income.

Tax Evasion: A failure to pay or a deliberate underpayment of taxes.

Terminal: Storage facility used in the wholesale segment of the industry, usually comprised of a gathering of large-capacity tanks.

Transmix: also known as interface, the product removed from a pipeline system between two separate product batches that cannot be blended with the first or second product.

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Wholesale or Jobber: A person who purchases tax-paid gasoline for resale or distribution at wholesale.

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