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Engine Classification: A 2-digit numeric code identifying vehicle engines by the number of cylinders. (GSA2)

Engine Displacement: (See also Cylinder, Engine Size) The volume in inches, through which the head of the piston moves, multiplied by the number of cylinders in the engine. Also known as cubic inch displacement (CID), may also be measured in liters. (GSA2)

Engine Retarder: Electronic equipment which governs engine speed control. (BOC3)

Engine Size: (See also Cylinder, Engine Displacement) The total volume within all cylinders of an engine, when pistons are at their lowest positions. The engine is usually measured in "liters" or "cubic inches of displacement (CID)." Generally, larger engines result in greater engine power, but less fuel efficiency. There are 61.024 cubic inches in a liter. (DOE4) (DOE5)

Engineer: A person responsible for operating and maintaining the power system on a vessel. (TNDOT1)

English Units: The term "English" refers to the United States legislative interpretation of the units as defined in a document prepared by the National Institute of Standards and Technology (NIST), U.S. Department of Commerce, Special Publication 330. Commonly used English units in Highway Performance Monitoring System (HPMS) are miles, feet, and inches. (FHWA2)

ENOD: Employee Not on Duty (FRA4)

Enplaned Passenger: The total number of revenue passengers boarding aircraft. (FAA15)

Enplaned Revenue Tons of Freight and Mail: The number of revenue tons of freight and mail loaded on an aircraft including originating and transfer tons. (FAA15)

Enplanement: Domestic, territorial, and international revenue passengers who board an aircraft in the states in scheduled and non-scheduled service of aircraft in intrastate, interstate, and foreign commerce and includes intransit passengers (passengers on board international flights that transit an airport in the US for non-traffic purposes). (FAA11)

ENTERPRISE: Evaluating New Technologies for Roads Program Initiatives in Safety and Efficiency (FHWA15)

Entitlement: See Apportionment.

Entrapment: Refers to persons being partially or completely in the vehicle and mechanically restrained by a damaged vehicle component. Jammed doors and immobilizing injuries, by themselves, do not constitute entrapment. Occupants pinned by cargo shift are not considered to be entrapped. Occupants who are completely or partially ejected and subsequently become pinned by their own vehicle and any surface other than their own vehicle are not considered entrapped. An occupant whose seat belt buckle release mechanism is jammed as a result of a crash is not considered entrapped. (NHTSA2)

Entry Point: The point at which an aircraft transitions from an offshore control area to oceanic airspace. (FAA4)

Environmental Protection Agency Certification Files: Computer files produced by Environmental Protection Agency (EPA) for analysis purposes. For each vehicle make, model and year, the files contain the EPA test Miles Per Gallon (MPG) (city, highway and 55/45 composite). These MPG's are associated with various combinations of engine and drive-train technologies (e.g., number of cylinders, engine size, gasoline or diesel fuel, and automatic or manual transmission). These files also contain information similar to that in the Department of Energy (DOE)/EPA Gas Mileage Guide, although the MPG's in that publication are adjusted for shortfall. (DOE4) (DOE5)

Environmental Protection Agency Composite Mile Per Gallon (MPG): The harmonic mean of the Environmental Protection Agency (EPA) city and highway MPG, weighted under the assumption of 55 percent city driving and 45 percent highway driving. (DOE4) (DOE5)

Environmental Restoration: Restitution for the loss, damage, or destruction of natural resources arising out of the accidental discharge, dispersal, release or escape into or upon the land, atmosphere, watercourse, or body of water of any commodity transported by a motor carrier. This shall include the cost of removal and the cost of necessary measure taken to minimize or mitigate damage to human health, the natural environment, fish, shellfish, and wildlife. (49CFR387)

Environmentally Sensitive Area: An area of environmental importance which is in or adjacent to navigable waters. (49CFR194)

EOD: Employee on Duty (FRA4)

EOF: Emergency Operations Facility (FAA17)

EPA: Environmental Protection Agency (BTS2) (OFR1)

EPACT: Energy Policy Act of 1992 (BTS8)

EPS: Engineered Performance Standards (FAA4)

Equalizing Reservoir: An air reservoir connected with and adding volume to the top portion of the equalizing piston chamber of the automatic brake valve, to provide uniform service reductions in brake pipe pressure regardless of the length of the train. (49CFR236)

Equipment Code: A six digit numeric code used to classify equipment by its usage characteristics (passenger carrying, cargo hauling, etc.), gross weight rating, and equipment configuration (panel truck, pick-up, stake body, dump etc.). (GSA2)

Equipment Consist: An equipment consist is a train, locomotive(s), cut of cars, or a single car not coupled to another car or locomotive. (FRA2) (FRA4)

Equipment Damage: All costs, including labor and material, associated with the repair or replacement-in-kind of on-track rail equipment. Trailers/container on flat cars are considered to be lading and damage to these is not to be included in on-track equipment damage. Damage to a flat car carrying a trailer/container is to be included in reportable damage. (FRA2)

Equivalent Airspeed: The calibrated airspeed of an aircraft corrected for adiabatic compressible flow for the particular altitude. Equivalent airspeed is equal to calibrated airspeed in standard atmosphere at sea level. (14CFR1)

ERG: Emergency Response Guide (RSPA2)

ERGS: Electronic Route Guidance System (FHWA15)

ERM: En Route Metering (FAA19)

ERP: Enroute Reporting Point (MTMC1)

ESAL: Equivalent Single-Axle Load (MM)

ESARTS: En Route Stand-Alone Radar Training System (FAA19)

ESMMC: Enhanced SMMC (FAA19)

ESP: En Route Spacing Program (FAA4) (FAA17) (FAA19)

ESP: Extra - Sensory Perception

Establishment: A single physical location where business is conducted or where services or industrial operations are performed. Examples of railroad establishments include, but are not limited to: an operating division; general office; and a major installation such as a locomotive or car repair or construction facility. For employees who are engaged in dispersed operations, such as track maintenance workers, the "establishment' is the location where these employees report for work assignments. (FRA2)

Estimate Ratio: (See also Mean; Ratio Estimate) The ratio of two population aggregates (totals). For example, "average miles traveled per vehicle" is the ratio of total miles driven by all vehicles, over the total number of vehicles, within any subgroup. There are two types of ratio estimates; those computed using aggregates for vehicles and those computed using aggregates for households. (DOE5)

Estimated Arrival Time: The time the flight is estimated to arrive at the gate (scheduled operators) or the actual runway on times for nonscheduled operators. (FAA4)

Estimated Elapsed Time: The estimated time required to proceed from one significant point to another. (FAA4)

Estimated En Route Time: The estimated flying time from departure point to destination (lift-off to touchdown). (FAA4)

Estuary: The lower end of a river, or a semi-enclosed coastal body of water with access to the open ocean, which is affected by the tides and where fresh and salt water mix. (DOI3)

ETA: Estimated Time of Arrival (FAA4) (FAA8)

ETC: Electronic Toll Collection (FHWA11)

ETC: Employee Transportation Coordinator (MOCD)

ETE: Estimated Time En Route (FAA4)

Ethanol: Otherwise known as ethyl alcohol, alcohol, or grain-spirit. A clear, colorless, flammable oxygenated hydrocarbon with a boiling point of 78.5 degrees Celsius in the anhydrous state. In transportation, ethanol is used as a vehicle fuel by itself (E100), blended with gasoline (E85), or as a gasoline octane enhancer and oxygenate (10% concentration). (DOE6)

ETMS: Enhanced Traffic Management System (FAA17) (FAA7) (FAA19)

ETOPS: Extended Twin-Engine Over Water Operations (OST3)

ETRR: Export Traffic Release Request (MTMC1)

ETTM: Electronic Toll and Traffic Management (TXDOT)

ETV: Electronic Transfer Vehicle (MTMC1)

ETVS: Enhanced Terminal Voice Switching (FAA19)

EUR: European Region (USTTA1)

EV: Electric Vehicle (BTS8)

EVAS: Enhanced Vortex Advisory System (FAA17)

Event: See also Accident, Casualty, Collision, Crash, Derailment, Fatality, Incident, Injury.

Event Recorder: A device, designed to resist tampering, that monitors and records data on train speed, direction of motion, time, distance, throttle position, brake applications and operations (including train brake, independent brake, and, if so equipped, dynamic brake applications and operations) and, where the locomotive is so equipped, cab signal aspect(s), over the most recent 48 hours of operation of the electrical system of the locomotive on which it is installed. (49CFR229)

EWR: Newark International Airport (FAA11)

Ex Quay: The seller makes the goods available to the buyer on the quay (wharf) at the destination named in the sales contract. The seller has to bear the full cost and risk involved in bringing the goods there. (USTTA1)

Ex Ship: The seller will make the goods available to the buyer on board the ship at the destination named in the sales contract. The seller bears all costs and risks involved in bringing the goods to the destination. (USTTA1)

Ex Ship's Tackle (EST): Similar to Cost, Insurance and Freight, but seller is responsible for loss and damage until goods are delivered on dock at port of destination. Seller has to insure goods up to this point. Also called "ex ship." (TNDOT1)

Ex Warehouse: Buyer is responsible for all charges to destination and has to arrange insurance to cover the goods from the time they leave the warehouse at the place of shipment until their arrival at final destination. Also called "ex works." (TNDOT1)

Ex Works: See Ex Warehouse.

Excess: Any property under the control of a Federal Agency which that agency determines is not required for its needs or for the discharge of its responsibilities. (GSA2)

Excess Baggage Revenue: Revenues from the transportation by air of passenger baggage in excess of the free allowance. (BTS4)

Exclusion Zone: An area surrounding a Liquified Natural Gas (LNG) facility in which an operator or government agency legally controls all activities in accordance with 49 CFR 193.2057 and 49 CFR 193.2059 for as long as the facility is in operation. (49CFR193)

Exclusive Right-Of-Way: (See also Controlled Access Rights-of-Way) A highway or other facility that can only be used by buses or other transit vehicles. (APTA1)

Exclusive Rights-Of-Way: Roadways or other right-of-way reserved at all times for transit use and/or other high occupancy vehicles. The restriction must be sufficiently enforced so that 95 percent of vehicles using the right-of-way are authorized to use it. (FTA1)

Executive Transportation: Any use of an aircraft by a corporation, company, or other organization for the purposes of transporting its employees and/or property not for compensation or hire, and employing professional pilots for the operation of the aircraft. (FAA2) (FAA10) (FAA14)

Exempt Carrier: A for hire interstate operator [which] transports commodities or provides types of services that are exempt from federal regulation, could also operate within exempt commercial zones. (BOC4)

Exempt Intracity Zone: The geographic area of a municipality or the commercial zone of that municipality described by the Interstate Commerce Commission (ICC) in 49 CFR 1048, revised as of October 1, 1975. The descriptions are printed in appendix F to subchapter B of 49 CFR, Chapter III, Subchapter B. The term "exempt intracity zone" does not include any municipality or commercial zone in the State of Hawaii. For the purposes of 49 CFR 390.3(g), a driver may be considered to operate a vehicle wholly within an exempt intracity zone notwithstanding any common control, management, or arrangement for a continuous carriage or shipment to or from a point without such zone. (49CFR390)

Exempt Motor Carrier: A person engaged in transportation exempt from economic regulation by the Interstate Commerce Commission (ICC) under 49 U.S.C. 10526. "Exempt motor carriers" are subject to the safety regulations set forth in 49 CFR, Chapter III, Subchapter B. (49CFR390)

Exemption: A temporary or permanent grant, license or form of legal permission given by an agency to deviate from a regulation or provision of law administered by that agency. Issued in response to a petition for relief submitted by an individual or company. (USCG1)

Expandable: Flatbed trailer which can be expanded beyond its regular length to carry larger shipments. (ATA1)

Expect Altitude At Time or Fix: Used under certain conditions to provide a pilot with an altitude to be used in the event of two-way communications failure. It also provides altitude information to assist the pilot in planning. (FAA4)

Expect Further Clearance: Used to inform a pilot of the routing he can expect if any part of the route beyond a short range clearance limit differs from that filed. (FAA4)

Expected Departure Clearance Time (EDCT): The runway release time assigned to an aircraft in a controlled departure time program and shown on the flight progress strip as an EDCT. (FAA4)

Expedite: Used by Air Traffic Control (ATC) when prompt compliance is required to avoid the development of an imminent situation. (FAA4)

Expenditure: All amounts of money paid out by a government, net of recoveries and other correcting transactions, other than retirement of debt, investment in securities, extension of credit, or agency transactions. Federal expenditures are also referred to as outlays. (BTS3)

Expenditures: Funds spent for energy purchased and paid for or delivered to a manufacturer during a calendar year. The expenditure dollar includes state and local taxes and delivery charges. (DOE5)

Experimental Aircraft: An aircraft which does not have a type design or does not meet other certification standards. The "experimental" designation is one of several "Special Airworthiness Certificates" which allows the aircraft to operate in U.S. airspace. None may be used for commercial purposes. Experimental aircraft are divided into three groups: 1) amateur built: an aircraft, built by one or more persons who undertake the effort for the purpose of recreation and education; 2) exhibition: a unique (one-of-a-kind) aircraft, a replica, a foreign or U.S. military surplus aircraft which may be used for exhibition purposes-movie and television productions, or sanctioned, organized events where the unique or unusual characteristics of the aircraft can be displayed; 3) other: includes experimental aircraft that are not amateur or exhibition. This includes aircraft involved in research and development, crew training, market surveys, air racing, those used to show compliance with regulations and the like. (FAA6)

Explosion-Detonation: An accident/incident caused by the detonation of material carried by or transported by rail. A detonation occurs when a shock wave exceeds the speed of sound. Explosions-detonations resulting from mishaps during loading or unloading operations, and those caused by fire aboard on-track equipment are included in this definition. (FRA2)

Export License: A government document permitting designated goods to be shipped out of the country as specified. (TNDOT1)

Exports: 1) Outbound international freight, including re-export of foreign merchandise. 2) Shipments of goods from the 50 States and the District of Columbia to foreign countries and to Puerto Rico, the Virgin Islands, and other U.S. possessions and territories. (DOE3) (DOE5) (TNDOT1)

Exposed Pipeline: A pipeline where the top of the pipe is protruding above the seabed in water less than 15 feet deep, as measured from the mean low water. (49CFR195)

Express Body: Open box truck body. (ATA1)

Express Bus: A bus that operates a portion of the route without stops or with a limited number of stops. (APTA1)

Expressway: (See also Freeway, Freeways and Expressways, Highway, Interstate Highway (Freeway or Expressway), Road). A divided highway for through traffic with full or partial access control and including grade separations at all or most major intersections. (FHWA2)

Extended Over-Water Operations: 1) With respect to aircraft other than helicopters, an operation over water at a horizontal distance of more than 50 nautical miles from the nearest shoreline; and 2) With respect to helicopters, an operation over water at a horizontal distance of more than 50 nautical miles from the nearest shoreline and more than 50 nautical miles from an off-shore heliport structure. (14CFR1)

External Combustion Engine: An engine in which fuel combustion takes place outside the cylinder, turbine, or the like and in which energy is turned into mechanical force; for example, a steam engine. (TRB1)

External Load: A load that is carried, or extends, outside of the aircraft fuselage. (14CFR1)

External Load Attaching: The structural components used to attach an external load to an aircraft, including external-load containers, the backup structure at the attachment points, and any quick-release device used to jettison the external load. (14CFR1)

Extraordinary Items Income (Loss): Income or loss which can be characterized as material, unusual and of infrequent occurrence. (BTS4)


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