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Glossary of Truck Industry Terms, E – I (Including FMCSR)


Eastern Turnpike Double.
Vehicle with nine axles consisting of a tractor and two 45- 48 foot trailers.

Edge Protector.
A device placed on the exposed edge of an article to distribute tiedown forces over a larger area of cargo than the tiedown itself, to protect the tie-down and/or cargo from damage, and to allow the tiedown to slide freely when being tensioned.

EDI (Electronic Data Interchange).
The business-to-business interconnection of computers for the rapid exchange of a wide variety of documents, from bills of lading to build tickets at auto plants.

Effective Peripheral Grip.
Any shaped surface, free of sharp edges, in which a full grasp can be made to secure a handhold by a person.

Eight Consecutive Days.
The period of 8 consecutive days beginning on any day at the time designated by the motor carrier for a 24-hour period.

Electrical Retarder.
Uses electromagnets to slow the rotors attached to the drive train. The driver turns it on or off with a switch in the cab.

Electrical System.
Provides electricity to power the charging, cranking, ignition, lighting and accessory circuits.

Eligible Unit of Local Government.
A city, town, borough, county, parish, district, or other public body created by or pursuant to State law which has a total population of 3,000 individuals or less.

Embargo to resist or prohibit the acceptance and handling of freight.
A formal notice that certain freight will not be accepted.

Any hurricane, tornado, storm (e.g. thunderstorm, snowstorm, ice storm, blizzard, sandstorm, etc.) high water, wind-driven water, tidal wave, tsunami, earthquake, volcanic eruption, mud slide, drought, forest fire, explosion, blackout or other occurrence, natural or man-made, which interrupts the delivery of essential services (such as electricity, medical care, sewer, water, telecommunications, and telecommunication transmissions) or essential supplies (such as, food and fuel) or otherwise immediately threatens human life or public welfare, provided such hurricane, tornado, or other event results in:
(1) A declaration of an emergency by the President of the United States, the Governor of a State, or their authorized representatives having authority to declare emergencies; by the Regional Director of Motor Carriers of Motor Carriers for the region in which the occurrence happens; or by other Federal, State or local government officials having authority to declare emergencies, or
(2) A request by a police officer for tow trucks to move wrecked or disabled motor vehicles.

Emergency Brake Release.
Will override the spring brake control in the event air pressure is lost. You must hold it while pulling out on the spring brake control. For emergency use only.

Emergency Brake System.
Secondary braking system used to stop a vehicle if the main braking system fails.

Emergency Brake System.
A mechanism designed to stop a vehicle after a single failure occurs in the service brake system of a pat designed to contain compressed air or brake fluid or vacuum (except failure of a common valve, manifold brake fluid housing or brake chamber housing).

Emergency Engine Stop Control.
Shuts down the engine. Use this control in emergency situations only. Many companies insist that it be reset by a mechanic after each use.

Emergency Equipment.
Equipment needed during an emergency. For a CMV, the emergency equipment consists of a fire extinguisher, reflective emergency triangles, fuses if needed, tire change kit, accident notification kit, and a lit of emergency numbers. It is also good to have extra food, drinking water, medicine, extra clothes and cold weather outerwear.

Emergency Movement.
Movement by motor carrier in an instance which isn’t covered by ordinary circumstances, law, regulation or permit, which usually requires the acquisition of authority from a regulatory body.

Emergency Relay Valve.
Relays air form the trailer air tank to the brake chambers. If there is a break in the lines between the tractor and trailer, the valve sends air form the trailer reservoir to the brake chambers.

Emergency Relief.
An operation in which a motor carrier or driver of a commercial motor vehicle is providing direct assistance to supplement State and local efforts and capabilities to save lives or property or to protect public health and safety as a result of an emergency as defined in this section.

Emergency Stopping.
Stopping quickly while keeping the vehicle under control.

Emergency Triangles.
Reflective triangles to be carried on all current commercial vehicles and required by law under FMCSR 393.95.

Refers to gases and other materials vented to the atmosphere by the exhaust system.

Any individual, other than an employer, who is employed by an employer and who in the course of his or her employment directly affects commercial motor vehicle safety. Such term includes a river of a commercial motor vehicle (including an independent contractor while in the course of operating a commercial motor vehicle, a mechanic, and a freight handler. Such term does not include an employee of the United States, any State, any political subdivision of a State, or any agency established under a compact between States and approved by the Congress of the United States who is acting within the course of such employment.

Any person who is designated in a DOT agency regulation as subject to drug testing and/or alcohol testing. The term includes individuals currently performing safety-sensitive functions designated in DOT agency regulations and applicants for employment subject to pre-employment testing. For purposes of drug testing under this part, the term employee has the same meaning as the term “donor” as found on CCF and related guidance materials produced by the Department of Health and Human Services.

Any operator of a commercial motor vehicle, including full time, regularly employed drivers; casual, intermittent or occasional drivers; leased drivers and independent, owner-operator contractors (while in the course of operating a commercial motor vehicle) who are either directly employed by or under lease to an employer.

An individual designated in a DOT agency regulation as subject to rug testing and/or alcohol testing. As used in this part “employee” includes an applicant for employment. “Employee” and “individual” or “individual to be tested” have the same meaning for purposes of this part.

Any person (including the United States, a State, District of Columbia, tribal government, or a political subdivision of a State) who owns or leases a commercial motor vehicle or assigns persons to operate such a vehicle. The term employer includes an employer’s agents, officers and representatives.

Any person (including the United States, a State, District of Columbia, tribal government, or a political subdivision of a State) who owns or leases a commercial motor vehicle or assigns employees to operate such a vehicle.

Any person engaged in a business affecting interstate commerce who owns or leases a commercial motor vehicle in connection with that business, or assigns employees to operate it, but such terms does not include the United States, any State, any political subdivision of a State, or an agency established under a compact between States approved by the Congress of the United States.

A person or entity employing one or more employees (including an individual who is self-employed) that is subject to DOT agency regulations requiring compliance with this part. The term, as used in this part, means the entity responsible for overall implementation of DOT drug and alcohol program requirements, including individuals employed by the entity who take personnel actions resulting from violations of this part and any applicable DOT agency regulations. Service agents are not employers for the purposes of this part.

Employer-Employee Relations.
How a truck driver gets along with his/her employer.

The act of intruding or going beyond the proper limits, such as encroachment on another lane of traffic or off-tracking.

An amendment to an insurance policy.

An authorization to an individual’s CDL required to permit the individual to operate certain types of commercial motor vehicles.

Engine Block.
Houses the pistons.

Engine Brake.
Retarder alters valve timing and turns the engine into an air compressor. It can be operated by hand with a switch on the dash or automatically when the foot is removed form the accelerator pedal.

Engine Compartment.
Area where engine is kept. Check to see that it has been properly serviced. Look for signs of damage or possible problems with the engine, steering mechanism, and suspension system.

Engine Controls.
Start the engine and shut it down.

Engine Oil Temperature Gauge.
Indicates the temperature of the engine oil. The normal operating temperature for engine oil is 180-225 degrees.

Engine Shutdown.
The period of time from stopping the rig until the engine is turned off. Shutting down an engine requires a cooling off period. This prevents damage if the engine has a turbo-charger.

Engine Stop Control Knob.
Used in some diesel engines to shut off the engine. You pull the knob out and hold it until the engine stops.

Engine Water Jackets.
Hollow chambers that surround the cylinder liners and other parts exposed to high temperatures in the engine. The coolant circulates within these chambers to cool the engine.

En Route Inspection.
A rig’s control and instrument check while driving and a check of critical items at each stop.

The area around the rig that you must see, hear, feel and sense when driving.

Environmental Protection Agency (EPA).
Regulates hazardous materials.

Environmental Restoration.
Restitution for the loss, damage, or d 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.

Error Correction Training.
Training provided to BATs, collectors, and screening test technicians (STTs) following an error that resulted in the cancellation of a drug or alcohol test. Error correction training must be provided in person or by a means that provides real time observation and interaction between the instructor and trainee.

Escape Ramps.
Areas used to stop runaway rigs by either sinking the rig in loose gravel or sand or sending it up an incline. They are designed to stop a vehicle safely without injuring people or damaging the cargo.

Evasive Steering.
Steering out of an emergency situation.

Evidence of Security.
A surety bond or a policy of insurance with the appropriate endorsement attached.

Evidential Breath Testing Device (EBT).
A device approved by NHTSA for the evidential testing of breath at the .02 and .04 alcohol concentrations, placed on NHTSA’s Conforming Products List (CPL) for “Evidential Breath Measurement Devices” and identified on the CPL as conforming with the model specifications available from NHTSA’s Traffic Safety Program.

Excess Freight.
Freight in excess of the quantity shown on the freight bill.

Exempt Carrier.
Company which transports commodities exempted from Interstate Commerce Commission (ICC) economic regulation, i.e. farm products, some fish products.

Exempt Carrier.
Motor carrier engaged in for-hire transportation of commodities exempt from federal economic regulation under 49 USC 13506 and 49 CFR 372.115.

Exempt Commodity Carrier.
Carriers that haul commodities, intrastate or interstate, exempt from regulations, such as fresh fruit (except bananas) and vegetables.

Exempt Intracity Zone.
The geographic area of a municipality or the commercial zone of that municipality described by the FHWA in 49 CFR part 372, subpart B. The descriptions are printed in appendix F to subchapter B of this chapter. The term “exempt intracity zone” does not include any municipality or commercial zone in the State of Hawaii. For purposes of 391.2(d), a driver may be considered to operate a commercial motor 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.

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 this subchapter.

Physical activity that elevates the heart rate, strengthens muscles and burns calories.

Exhaust Brake.
Designed to restrict the flow of engine exhaust gases, increasing the retarding effect of the engine and resulting in slowing of the vehicle.

Exhaust Brake.
A retarder that keeps the exhaust gases from escaping which creates pressure that keeps the engine from increasing speed. It is controlled by an on/off switch in the cab or automatically by a switch on the accelerator or clutch pedal.

Exhaust Manifold.
That part of the exhaust system that carries the exhaust gases from the cylinders to the turbocharger.

Exhaust Ports.
Connecting passages from the inside to the outside of the cylinder heads.

Exhaust Pyrometer Gauge.
Indicates the temperature of the gases in the exhaust manifold. Maximum safe operating temperatures may be shown on the pyrometer name plate or listed in the operator’s manual.

Exhaust Stack.
Pipe connected to the muffler through which exhaust gases are released.

Exhaust Stroke.
The last phase of the four-stroke cycle when waste gases are pushed out of the exhaust valve.

Exhaust System.
Required on all motor vehicles and used to discharge gases created by the operation of the engine. These fumes could be deadly if they get into the cab or sleep berth. For safety, do not operate a vehicle with missing, loose, or broken exhaust pipes, mufflers, tailpipes, or vertical stacks.

Exhaust Valves.
Open to discharge the burned gases from the combustion chambers.

To send goods to a foreign country.

Extended Hood.
A conventional tractor, only with a longer hood.

Extreme Driving Conditions.
Hazardous conditions created by weather such as snow, rain, or ice, or by difficult terrain such as mountains.

Eye Lead Time.
Term used to describe the distance that a driver is looking ahead on the road. A 12-second eye lead time means that the driver is looking ahead the distance he/she will travel in 12 seconds time.

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Fan Belt.
A belt from the engine that drives the fan.

Farm Vehicle Driver.
A person who drives only a commercial motor vehicle that is:
(a) Controlled and operated by a farmer as a private motor carrier of property;
(b) Being used to transport either:(1) Agricultural products, or(2) Farm machinery, farm supplies, or both, to or from a farm;
(c) Not being used in the operation of a for hire motor carrier;
(d) Not carrying hazardous materials of a type or quantity that requires the commercial vehicle to be placarded in accordance with 177.823 of this subtitle; and
(e) Being used within 150 air-miles of the farmer’s farm.

Any person who operates a farm or is directly involved in the cultivation of land, crops, livestock which:
(a) Are owned by that person; or
(b) Are under the direct control of that person.

The death of a person as a result of a motor vehicle accident.

Being very tired from overwork, stress, or lack of sleep.

Federal Communications Commission.

Federal Bridge Formula.
A formula used to figure permissible gross loads. It also requires minimum distances between the tractor and trailer axles.

Federal Hazardous Materials Regulations (FMHRs).
Those safety regulations which are contained in parts 107, 171-173, 177, 178 and 180, except part 107 and 107.15 and 171.16.

Federal Highway Administrator (the Administrator).
The chief executive of the Federal Highway Administration, an agency within the Department of Transportation.

Federal Motor Carrier Safety Administration (FMCSA).
An administration within the U.S. Department of Transportation. FMCSA’s primary mission is to reduce crashes, injuries, and fatalities involving large trucks and buses. FMCSA develops and enforces the Federal Motor Carrier Safety Regulations (FMCSRs).

Federal Motor Carrier Safety Regulations (FMCSRs).
Those safety regulations which are contained in parts 390, 391, 392, 393, 395, 396, and 397 of this subchapter.

Federal Regulations for Hazardous Materials Transport.
Federal laws that regulate the manner in which hazardous materials must be shipped.

Federal Register.
Government publication that prints rules/regulations of federal agencies on a daily basis.

An offense under State or Federal law that is punishable by death or imprisonment for a term exceeding 1 year.

Fender Mirror.
Is mounted on the fender of a regular long nose tractor. Requires less eye movement and makes it easier to watch ahead of you. Wide angle fender mirrors let you see more when you are making right turns.

The Federal Highway Administration, an agency within the Department of Transportation.

Field of View.
The area that you can see either in front of you or behind you with your mirrors.

Field of Vision.
Everything you can see (front and both sides) while looking straight ahead.

Fifth wheel.
A device mounted on a truck tractor or similar towing vehicle (e.g., converter dolly) which interfaces with and couples to the upper coupler assembly of a semi trailer.

Fifth Wheel.
Coupling device designed to connect the semi-trailer to the tractor. The fifth wheel is located on the rear frame of the tractor and consists of a flat rounded plate with a locking bar mounted on the tractor and a kingpin attached to the semi-trailer. The fifth wheel bears the weight of the front half of the semi-trailer and provides freedom for articulation.

Fifth wheel.
Used to connect the trailer to the tractor. It should be properly lubricated, and there should be no worn or loose parts. Also check that there is not too much slack in the kingpin locking jaws.

Fifth Wheel Anti-Jackknife Device.
Prevents a collision between the trailer and the cab. It is automatic and restricts the rotation of the kingpin.

Fifth Wheel Plate.
Plate located on the front underside of the trailer, fastened to the bottom of the trailer floor and resting on the fifth-wheel. It supports the weight of the nose of the semi-trailer and the cargo inside. See also Cast Steel Top Plate, Stamped Steel Top Plate, Fixed Fifth Wheel, Manual Sliding Fifth Wheel, Air Slide Fifth Wheel.

Final Agency Order.
A notice of final agency action issued pursuant to part 386 by either the appropriate FMCSA Field Administrator (for default judgments under 386.14(e)), the FMCSA Chief Safety Officer, or an Administrative Law Judge (ALJ), typically requiring payment of a civil penalty by a broker, freight forwarder, driver or motor carrier.

Financial Responsibility.
The financial reserves (e.g. insurance policies or surety bonds) sufficient to satisfy liability amounts set forth in this subpart covering public liability.

Fingertip Grasp.
A handhold surface which provides a person contact restricted to finger segments 1 and/or 2 only; or which limits wrap-around closure of finger segment 1 with the palm of the hand to 90 degrees.

Fire Extinguishers.
Used to put out fires, usually marked by a letter and symbol to indicate the classes of fires for which it can be used. Every truck or truck tractor with a gross vehicle weight rating (GVR) of 10,001 pounds or more must have a fire extinguisher.

First Aid.
Immediate and temporary care given to a victim until professional help arrives.

Fixed Fifth Wheel.
A fifth wheel whose position is not adjustable since it is bolted directly to the truck frame.

Fixed or Stationary Trailer Tandem Axle Assembly.
Is a tandem axle that is placed to get the best weight distribution between the tractor and the trailer, but cannot be moved. Weight adjustments between the tractor and the trailer are then made by moving, or shifting, the load inside the trailer.

Fixed Tandem.
Assembly of two axles and suspension that is attached to the chassis in one place, and cannot be moved fore and aft.

Fixed-Mount Fifth Wheel.
The fifth wheel that is secured in a fixed position behind the cab.

Trailer with level bed and no sides or top.

Flatbed Trailer.
A semi-trailer with no sides, top or end above the platform of the trailer.

Flexible Brake Hose.
High-pressure line which connects the brake line from the master cylinder to the wheel cylinder.

Trailers with detachable container bodies that are loaded on specially constructed flat cars equipped with two turntables.

Float Shifting.
Slang for gear changing without use of the clutch.

Flotation Tire.
A wide –based tire that is used at extremely low pressures.

The Federal Motor Carrier Safety Administration.

Federal Motor Carrier Safety Regulations (49 CFR parts 350-399).

FMCSR 392.4.
Prohibits driving while under the influence of any dangerous drug. These drugs include: narcotics, morphine, heroin, codeine, and amphetamines.

FMCSR 397.
Regulations that deal with driving and parking vehicles with hazardous materials.

FMCSR 397.3.
Requires all vehicles carrying hazardous materials to comply with state and local restrictions on routes and parking.

FMCSR 397.9.
Controls the routes of HAZMAT carriers. Trips must be planned in the best interest of public safety.

FMCSR, part 396, Inspection, Repair and Maintenance of Motor Vehicles.
Where you can find out-of-service regulations. By law you must know the requirements of FMCSR 396.9 (c). Motor Vehicle Declared Out-of-Service.

Fog Lamps.
Amber colored auxiliary lights for use during foggy and misty conditions.

Foot Brake Control Valve (also called foot valve or treadle valve).
This valve operates the service brakes on both the tractor and trailer.

Foot Brake Valve.
Valve which the driver depresses with his foot, which controls the amount of air pressure delivered to or released from the brake chambers. Also called a treadle valve.

Foot Valve.
A valve that is mounted either on the floor or fire wall of the cab and operates both the tractor and trailer air brakes when depressed.

For-Hire Carrier.
A company in the business of transporting product belonging to others.

Force Majeure.
A defense protecting the parties in the event that a part of the contract cannot be performed due to causes which are outside the control of the parties and could not be avoided by exercise of due care.

Force of Motion.
Movement determined by the weight and speed of an object as it moves along.

Outside the fifty United States and the District of Columbia.

For-Hire Carriage.
Motor carrier services in which charge is made to cover cost of transportation, generally provided by common or contract carrier.

For-Hire Carrier.
An organization that has as its primary business hauling cargo by truck.

For-Hire Motor Carrier.
A person engaged in the transportation of goods or passengers for compensation.

Used for loading pallets and heavy objects.

Foundation Brake.
A type of brake designed with the brake shoes on the inside of the braking drum to expand against the inner surface of the drum. A common braking mechanism for trucks.

Four-axle, removable gooseneck, low bed with outriggers.
Has a low bed frame, four rear trailer axles and a detachable gooseneck and outriggers for wide loads.

Four-way Flashers.
Two amber lights at front and two amber lights or red lights at rear of vehicle. These are usually the front and rear turn signal lights, equipped to do double duty as warning lights. Make sure they are clean.

The metal infrastructure of any vehicle – creates the underpinnings to support the rest of the vehicle.

Frame Dump Trailer.
A type of dump truck in which there is a frame between the kingpin and axles that carries the load and provides strength and stability.

Frame Rails.
Steel beams that run the length of the tractor and trailer.

Frame Vehicle.
A vehicle with skeletal structure fitted with one or more bunk units for transporting logs. A bunk unit consists of U-shaped front and rear bunks that together cradle logs. The bunks are welded, gusseted or otherwise firmly fastened to the vehicle’s main beams, and are an integral part of the vehicle.

Frameless Dump Trailer.
A type of dump truck that has no frame but uses a platform to support its weight and cargo.

Frameless Construction.
The exterior of the van or tank is the weight-carrying part instead of the frame.

Free on board (F.O.B.).
Contractual terms between a buyer and a seller which define where title transfer takes place and the exchange point where responsibility for risk/expense transitions from seller to buyer.

Goods being transported from one place to another.

Freight Bills.
Bills prepared by the carrier from the bill of lading that must be signed by the consignee before the cargo can be unloaded and indicate whether the charges are prepaid or COD.

Freight Broker.
A person or company that arranges for transporting freight.

Freight Charge.
The rate established for transporting freight.

Freight Claim.
A charge made against a carrier for loss, damage, delay or overcharge.

Freight Forwarder.
A person holding itself out to the general public (other than as an express, pipeline, rail, sleeping car, motor, or water carrier) to provide transportation of property for compensation in interstate commerce, and in the ordinary course of its business:
1) Performs or provides for assembling, consolidating, break-bulk, and distribution of shipments.
2) Assumes responsibility for transportation form place of receipt to destination; and
3) Uses for any part of the transportation a carrier subject to FMCSA jurisdiction.

Freight Forwarder.
A person who gathers small shipments from various shippers and puts them together into larger shipments. These shipments then may go to a break-bulk facility where they are broken down for delivery to the consignees.

Friction Mat.
A device placed between the deck of a vehicle and article of cargo, or between articles of cargo, intended to provide greater friction than exists naturally between these surfaces.

Front Brake Limiting Valve.
Sometimes controlled by a two-way switch mounted on the dashboard. Designed to limit the amount of braking force applied to the front axle brakes to avoid locking up the brakes on slippery surfaces. Found only on tractors with front axle air brakes.

Front Haul.
1) The front portion of a trip, from start to destination; or
2) Freight carried on the front portion of the trip.

Fuel Filters.
Clean the fuel as it goes from the entry tube of the tank, through the tank and fuel lines, and into the injectors. To keep containments out of the fuel system.

Fuel Gauge.
Shows how much fuel is in tanks. Since the gauge is not always accurate, a driver should check the tanks visually before each trip and at stopovers.

Fuel Pump.
Pump that moves a fuel from the fuel tank to the engine.

Fuel System.
Regulates the amount of fuel that is sent to the engine and how often it is injected into the cylinders.

Fuel System Heater.
Keeps the fuel system from freezing.

Fuel Tank.
Holds the fuel.

Fuel Tank Fitting.
Any removable device affixed to an opening in the fuel tank with the exception of the filler cap.

Fuel Tax.
A tax based on the number of miles driven in that state that is paid by the carrier to each state.

Full Flow System.
All oil leaving the oil pump passes through an oil filter.

Full Grasp.
A handhold surface which provides a person contact with finger segments 2 and 3 and which provides space for finger segment 1 to wrap around toward the palm of the hand beyond the 90-degree surface restriction. The handhold need not require contact between fingers and thumb.

Full Trailer.
Trailer that supports its entire weight and cargo on its own tires.

Full Trailer.
Is built so that no part of its weight rests upon the vehicle pulling and can fully support itself with its axles.

Furniture Van Body.
Truck body designed for the transportation of household goods; usually a van of drop-frame construction.

Completes the electrical circuit and prevents overheating by breaking a circuit.

A colored burning flare used as a signal to warn other road users.

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The acceleration due to gravity, 32.2 ft/sec 2 (9.823 m/sec 2).

GAW (Gross Axle Weight).
The total load a particular axle is supporting.

GAWR (Gross Axle Weight Rating).
Maximum weight an axle is rated to carry by the manufacturer, measured at tire-road interface. Measurement includes the axle weight and the portion of the vehicle carried by the axle.

GCW (Gross Combination Weight).
Total weight of the loaded combination vehicle including fuel, driver, trailer and cargo.

GCWR (Gross Combined Weight Rating).
Maximum combined safe weight of the vehicle as well as any towed or attached vehicles.

Gear Box Temperature Gauge.
Shows the temperature of the lubricant in the transmission. The normal reading is 150-200 degrees.

Gear Fast/Run Slow.
Term used in the industry to describe spec’ing a truck that will be geared to run at a high road speed but limited by the ECM to a certain speed to increase fuel economy.

Gear Pump.
Located at the rear of the fuel pump. Driven by the fuel pump main shaft. Consists of a single set of gears to pick up and deliver fuel throughout the fuel system. From gear pump, fuel flows through the filter screen and to the pressure regulator.

Gear Ratio.
The ratio of teeth or revolutions of one gear to the teeth or revolutions of the gear with which it is engaged.

Geared Speed.
The calculated speed of the vehicle based upon the engine’s rpms in each gear or top gear; the overall gear ratio to the driven wheels and the diameter of the driven wheels.

General Knowledge Test.
The written test all CDL applicants must take to see how much they know about the laws regulating the trucking industry.

Generators and Alternators.
Devices that recharge the battery when it loses electricity.

Glad Hands.
Mechanical couplings mounted on the front of the trailer to connect the air lines from the tractor to the trailer.

Glad Hands.
Connect the service and emergency air lines of the tractor to the trailer. The connections are secure when the glad hands lock.

Used to rest the trailer on the ground to load heavy equipment.

Gooseneck Trailer.
Drop deck trailer with a long narrow neck whose geometry permits the trailer to pivot without striking the truck.

Government Bill of Lading Shipper.
Any person whose property is transported under the terms and conditions of a government bill of lading issued by any department or agency of the Federal government to the carrier responsible for the transportation of the shipment.

Device designed to limit the maximum speed of the engine by controlling the fuel which limits the rpms; they are found mostly on diesel engines.

Regulates the air flow to maintain the desired pressure. When the air pressure approaches 125 psi (pounds per square inch), the inlet valves open. They will close again when the pressure drops below 110 psi.

Governor (fuel).
Maintains sufficient fuel for idling with the throttle control in “idle” position, and cuts off fuel above maximum rated RPM.

GPS (Global Positioning System).
Satellite system used to pinpoint a geographic position of the truck, tractor or trailer.

Steepness of a slope, expressed as a percentage. Example: a vehicle climbing a 5% grade rises 5 feet for every 100 feet horizontally.

The measure of a vehicle’s ability to climb an incline while maintaining a given speed.

Grain body.
Low side, open-top truck body designed to transport dry flowable commodities.

Gravity ramp.
Escape ramp that has a loose material surface with a grade of 5%-43%.

A device that serves as a support and protection to that which passes through it.

Gross Combination Vehicle Weight Rating (GCVWR).
The total weight of a tractor, trailer, and load.

Gross Combination Weight Rating (GCWR).
The value specified by the manufacturer as the loaded weight of a combination (articulated) vehicle. In the absence of a value specified by the manufacturer, GCWR will be determined by adding the GVWR of the power unit and the total weight of the towed unit and any load thereon.

Gross Combination Weight (GCW).
The weight of the tractor, trailer, and cargo.

Gross Horsepower.
The brake horsepower with the engine void of its accessories.

Gross Ton.
2,240 pounds. More commonly called a long ton.

Gross Vehicle Weight (GVW).
The total weight of a straight truck and load.

Gross Vehicle Weight Rating (GVWR).
The total weight of a tractor and all trailers.

Gross Weight.
1) The weight of an article together with the weight  of its container and the material used in packing;
2) As applied to a truck, the weight of a truck together with weight of its entire contents.

The flat horizontal surface on which the tires of a motor vehicle rest.

Ground Water Well Drilling Rig.
Any vehicle, machine, tractor, trailer, semi-trailer, or specialized mobile equipment propelled or drawn by mechanical power and used on highways to transport water well field operating equipment, including water well drilling and pump service rigs equipped to access ground water.

GVW (Gross Vehicle Weight).
Total weight of a vehicle and everything aboard, including its load.

GVWR (Gross Vehicle Weight Rating).
Maximum allowable weight of a commercial vehicle including the trailer and cargo; this figure is used in licensing the truck or trailer.

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A tractor having only a half of a cab along the left side of the engine.

Hand Valve.
A valve located on the steering column that is designed to apply only the trailer brakes.

That which qualifies as providing full grasp if a person is able to find a hand position on the handhold which allows more than fingertip grasp.

The surface area contacted by the hand when grasping a handhold. The size of this area is the width of the hand across the metacarpal and half the circumference of the handhold. The hand breadth of the typical person is 88.9 millimeters (3.5 inches).

Hand Truck.
Used to carry small loads from the trailer to a storage area.

Hand Valve.
The valve that controls only the trailer brakes.

Handling Brake.
Stopping the truck when the brakes fail.

Any road condition or road user (driver, cyclist, pedestrian, or animal) that presents a possible danger to you or your rig.

Hazard Warning Signal.
Lamps that flash simultaneously to the front and rear, on both the right and left sides of a commercial motor vehicle, to indicate to an approaching driver the presence of a vehicular hazard.

Hazardous Material.
Material that may pose a risk to health, safety and property while being transported.

Hazardous Materials.
Any material that has been designated as hazardous under 49 U.S.C. 5103 and is required to be placarded under subpart F of 49 CFR part 172 or any quantity of a material listed as a select agent or toxin in 42 CFR part 73.

Hazardous Material Shipping Papers.
Required and lists each item by the proper shipping name, hazard class, identification number, and packing group.

Hazardous Materials Endorsement.
An endorsement on a CDL that all drivers who transport hazardous materials must obtain.

Hazardous Materials Incident Report.
A written report that must be filed within 15 days if there is an unintended release of hazardous materials.

Hazardous Materials Regulations.
Standards set by the Research and Special Programs Administration (RSPA) Office of Hazardous Materials Transportation (OHMT) that regulate how hazardous materials are shipped.

Hazardous Materials Shipping Paper.
A bill of lading that describes hazardous materials by the proper shipping name, hazard class, identification number, and the quantity being shipped. This form must be legible.

Hazardous Substance.
A material, and its mixtures or solutions, that is identified in the appendix to 172.101, List of Hazardous Substances and Reportable Quantities, of this title when offered for transportation in one package, or in one transport motor vehicle if not packaged, and when the quantity of the material. Therein equals or exceeds the reportable quantity (RQ). This definition does not apply to petroleum products that are lubricants or fuels, or to mixtures or solutions of hazardous substances if in a concentration less than that shown in the table in 171.8 of this title, based on the reportable quantity (RQ) specified for the materials listed in the appendix to 172.101.

Hazardous Waste.
Any material that is subject to the hazardous waste manifest requirements of the EPA specified in 40 CFR part 262 or would be subject to these requirements absent an interim authorization to a State under 40 CFR part 123, subpart F.

Hazardous Waste Manifest.
A form (EPA-8700-22) that describes hazardous waste and identifies the shipper, carrier, and destination by name and by the identification numbers assigned by the EPA. The shipper prepares, dates, and signs the manifest. All carriers of the shipment must sign the paper. It must also be signed by the consignee. The driver keeps a copy.

Hazardous materials, as classified by the U.S. Environmental Protection Agency (EPA). Transport of hazardous materials is strictly regulated by the U.S. Department of Transportation.

Hazmat Labels.
Labels resembling small placards that are placed on packages near the proper shipping name and identification number.

Head Lamps.
Lamps used to provide general illumination ahead of a motor vehicle.

Headache Rack.
Heavy protective barrier mounted behind the tractor’s cab. It is designed to prevent injuries caused by load shifting forward from the trailer and crushing the cab. Useful place for hanging chains and equipment.

Headerboard (Headache Rack).
Protects the driver from the freight shifting or crushing him or her during a sudden stop and/or accident.

Header Bar.
A hinged, rear cross piece on open-top trailer, that can be swung out of the way to load high objects.

Two white lights, one to the right and one to the left on the front of the tractor – required on buses, trucks, and truck tractors. Used to  illuminate the vehicle to help the driver see and help others see the vehicle. During an inspection, make sure they are clean and both high and low beams work.

Any device or assembly of devices or appliances used to heat the interior of any motor vehicle. This includes a catalytic heater which must meet the requirements of 177.834(1) of this title when flammable liquid or gas is transported.

Heavy Hauler Trailer.
A trailer with one or more of the following characteristics:
(1) Its brake lines are designed to adapt to separation or extension of the vehicle frame; or
(2) Its body consists only of a platform whose primary cargo-carrying surface is not more than 40 inches above the ground in an unloaded condition, except that it may include sides that are designed to be easily removable and a permanent “front-end structure” as that term is used in Section 393.106 of this title.

Helper Service.
A helper is to be provided for loading or unloading freight. The bill of lading specifies who will pay for the helper.

The Department of Health and Human Services or any designee of the secretary, Department of Health and Human Services.

High Center of Gravity.
The bulk of the weight of the load is high off the ground.

High Cube Van.
Van whose body, wheel and tire design allows more space to give maximum loading area.

High Hitch.
This occurs when the trailer height is too high. As a result, the fifth wheel latches cannot properly grasp the kingpin.

High Priority Activity Funds.
Funds provided to States, local governments, and other persons carrying out activities and projects that directly support the MCSAP, are national ins cope in that the successful activity or project could potentially be applied in other States on a national scale, and improve CMV safety and compliance with CMV safety regulations. Up to 5 percent of total MCSAP funds are available for these activities.

Any road, street, or way, whether on public or private property, open to public travel. “Open to public travel” means that the road section is available, except during scheduled periods, extreme weather or emergency conditions, passable by four-wheel standard passenger cars, and open to the general public for use without restrictive gates, prohibitive signs, or regulations other than restrictions based on sized, weight or class of registration. Toll plazas of public toll roads are not considered restrictive gates.

The entire width between the boundary lines of every way publicly maintained when any part thereof is open to the use of the public for purposes of vehicular traffic.

Highway Valve.
Allows air from the hand valve to flow through the air line to put on only the trailer brakes.

HMR 177.810.
Requires drives of vehicles containing hazardous materials to obey state and local laws for the use of tunnels.

The Hazardous Materials Regulations (49 CFR parts 100-178).

Hook-Lift Container.
A specialized container, primarily used to contain and transport materials in the waste, recycling, construction/demolition and scrap industries, which is used in conjunction with specialized vehicles, in which the container is loaded and unloaded onto a tilt frame body by an articulating hook-arm.

Hopper Trailer.
Trailer designed with an open top for easy filling of grains and other bulk products. It is unloaded through doors in the bottom of the trailer.

Horsepower (hp).
Refers to the amount of work that can be done over a given amount of time; the measure of power defined by a rate of working of 33,000 foot-pounds per minute.

Horsepower, SAE Net.
Horsepower capability of an engine with full accessories and exhaust system. Test procedures per standards of Society of Automotive Engineers (SAE).

Hot Loads.
Rush shipment of cargo.

U.S. Department of Transportation safety regulations which govern the hours of service of commercial vehicle drivers engaged in interstate trucking operations.

The amount of time you may spend on duty.

Household Goods.
As used in connection with transportation, means the personal effects or property used, or to be used, in a dwelling, when part of the equipment or supplies of the dwelling. Transportation of the household goods must be arranged and paid for by the individual shipper or by another individual on behalf of the shipper. Household goods includes property moving from a factory or store if purchased with the intent to use in a dwelling and transported at the request of the householder, who also pays the transportation charges.

Household Goods Bill of Lading.
Used by moving companies for their shipments. This type of bill serves as a legal contract between the shipper and the carrier.

Household Goods Freight Forwarder (HHGFF).
A freight forwarder of household goods, unaccompanied baggage, or used automobiles.

Hub-Piloted Wheels.
A type of disc wheel that is centered by the close fit of the wheel center hole to the wheel hub.

Hydraulic Retarder.
A type of drive line retarder, mounted on the drive line between the engine and the fly wheel or between the transmission and drive axles that reduces speed by directing a flow of oil against the stator vanes. It can be turned on by hand with a lever in the cab or automatically by an accelerator switch on the floor.

A road condition in which a thin film of water separates the tires from the road and the rig simply slides along on top of the water.

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Interstate Commerce Commission.

Identification Lamps.
Lamps used to identify certain types of commercial motor vehicles.

Identification (ID) Number.
Four-digit numbers  used to identify all hazardous materials.

Letting the engine run while the rig is not moving.

Imminent hazard.
The existence of a condition that presents a substantial likelihood that death, serious illness, severe personal injury, or a substantial endangerment to health, property, or the environment may occur before the reasonably foreseeable completion date of a formal proceeding begun to lessen the risk of that death, illness, injury or endangerment.

In bond.
Storage of goods in custody of government/bonded warehouse or carrier from whom goods can be taken only upon payment of taxes/duties to an appropriate government agency.

In Bulk.
The transportation, as cargo, of property, except Division 1.1, 1.2, or 1.3 materials, and Division 2.3, Hazard Zone. A gases, in containment systems with capacities in excess of 3500 water gallons.

In Bulk (Division 1.1, 1.2, and 1.3 explosives). The transportation, as cargo, of any Division 1.1, 1.2, or 1.3 materials in any quantity.

In Bulk (Division 2.3, Hazard Zone A or Division 6.1, Packing Group I, Hazard Zone A materials).
The transportation, as cargo, of any Division 2.3, Hazard Zone A, or Division 6.1, packing Group I, Hazard Zone A material, in any quantity.

Incentive Funds.
Funds awarded to States achieving reductions in CMV involved fatal accidents, CMV fatal accident rate, or meeting specified CMV safety program performance criteria.

Independent Trailer Brake (trolley valve).
A hand valve that regulates the air flow to only the trailer unit and puts on the brakes. It is usually called the trolley valve and is normally on the right side of the steering column.

Independent Trucker.
One who owns a tractor and trailer and hauls products for self or others on either a regular or as needed basis.

Indian Tribe.
Has the same meaning as contained in 4 of the Indian Self-Determination and Education Act, 25 U.S.C. 450b.

Individual Shipper.
Any person who is the consignor or consignee of a household goods shipment identified as such in the bill of lading contract. The individual shipper owns the goods being transported and pays the transportation charges.

Individual Wheel Weight.
The load each wheel is supporting. It is usually checked by state or local officials with a  portable scale.

Indivisible Load.
Any vehicle or load which cannot be dismantled, disassembled, or loaded to meet specific regulatory limits for size and/or weight.

Initial Carrier.
The transportation line that picks up a shipment form the shipper; in other words, the “first” carrier.

Initial Drug Test (also known as a Screening drug test).
An immunoassay test to eliminate “negative” urine specimens from further consideration and to identify the presumptively positive specimens that require confirmation or further testing.

Initial Point.
The point at which a shipment originates.

Initial Validity Test.
The first test used to determine if a urine specimen is adulterated, diluted, or substituted.

A device found in a diesel engine that changes liquid fuel oil into a mist or spray and meters it to each cylinder.

Injector Pump.
A pump used to deliver fuel to the injectors under very high pressure.

Inner Bridge.
The distance between the center of the rearmost tractor axle and the center of the leading trailer axle. Determines weight limits.

Inside Delivery.
Indicates the freight is to be delivered inside instead of unloaded at the curb.

Inspection (Vehicle).
Checking over the vehicle parts and systems for problems and malfunctions and to see that everything is in order and in place. Pre-trip inspection is a thorough inspection done before the trip. En-route inspections are made periodically during the trip. Post-trip inspections are done after the trip, so that problems and malfunctions can be reported to maintenance personnel.

Inspection Routine.
List of steps you go through each time you inspect your vehicle so you do not forget a step.

Instruments and Gauges.
Make sure to check all instruments and gauges. In trucks with electronically controlled engine, the needles on all gauges will make a full sweep right after the engine is turned on to ensure all gauges are working.

Insurance Premium.
The monetary sum and insured pays an insurer for acceptance of liability for public liability claims made against the insured.

Insured and Principal.
The motor carrier named in the policy of insurance, surety bond, endorsement, or notice of cancellation, and also the fiduciary of such motor carrier.

Intake Manifold.
That part of the fuel system that carries the air or air/fuel mixture to the cylinders.

Intake Ports.
Provide the connecting passages from the outside of the cylinder heads to the inside head openings (the valves).

Intake Stroke.
Phase of the four-stroke cycle when fuel and air enter the cylinder.

Intake Valves.
Valves used in an engine to admit air into the combustion chambers of the cylinders.

Integral Securement System.
A system on certain roll-on/roll-off containers and hook-lift containers and their related transport vehicles in which compatible front and rear hold down devices are mated to provide securement of the complete vehicle and its articles of cargo.

Inter-Axle Differential.
A device designed to link tandem axles and to prevent slippage during icy or wet road conditions. It is also referred to as the power divider.

Inter-Axle Differential Lock Control.
Locks and unlocks rear tandem axles. In the locked position, keeps the wheels from spinning. This position is used on slippery roads.

Interchange Point.
A station at which freight in the course of transportation is delivered by one transportation line to another.

Transferring loaded trailer from one carrier to another to avoid loading/unloading. Daily rental/lease agreement usually used in this circumstance.

Interline Carrier.
One that accepts or delivers shipments for only part of the trip. Another carrier either begins or completes the trip.

Intermodal Transportation.
Using more than one mode to delivery a shipment.

Internal Combustion Engine.
Burns fuel within enclosed chambers called cylinders.International Registration Plan (IRP). An agreement among the states and Canadian provinces for paying registration fees that are based on the percentage of miles operated in each state or province.

Between states.

Interstate Commerce.
Trade, traffic, or transportation in the United States
1) Between a place in a sate and a place outside of such sate (including a place outside of the United States);
2) Between two places in a state through another state or a place outside of the United States; or
3) Between two places in a state as part of trade, traffic, or transportation originating or terminating outside the state or the United States.

Interstate Operating Authority.
Issued by the DOT. The right to transport regulated goods across state lines issued by the FMCSA and required by all for-hire interstate carriers of regulated commodities.

Interstate Routes.
These routes have separate opposing traffic, limited access, and bypass many small communities.

Interstate Transportation.
Transportation described at 49 U.S.C. 13501, and transportation in the United States otherwise exempt from the Secretary’s jurisdiction under 49 U.S.C. 13506(b)(1).

Within the state.

Intrastate Commerce.
The transportation of person or property between points within a state having origin, destination and all travel within the same state. A shipment between two points within a state may be interstate if the shipment had a prior or subsequent move outside of the state and the shipper intended an interstate shipment at origin.

Intrastate Operating Authority.
Permission granted by an individual state to conduct intrastate transportation within that state. Some states require authority registration for for-hire, private, and exempt carriers.

Invalid Drug Test.
The result of a drug test for a urine specimen that contains an unidentified adulterant or an unidentified interfering substance, has abnormal physical characteristics, or has an endogenous substance at an abnormal concentration that prevents the laboratory from completing or obtaining a valid drug test result.

Invalid Result.
The result reported by a laboratory for a urine specimen that contains an unidentified adulterant, contains an unidentified interfering substance, has an abnormal physical characteristic, or has an endogenous substance at an abnormal concentration that prevents the laboratory from completing testing or obtaining a valid drug test result.

A bill from the shipper that lists the goods, prices, and total due. This may be mailed to the consignee, or the driver may have to give it to the consignee if it is a COD shipment.

Irregular Route.
An irregular route describes long-distance transport between a combination of origin and destination points using any suitable route.

Issue and Issuance.
Initial licensure, license transfers, license renewals, license upgrades, and nonresident commercial driver’s licenses (CDLs) as described in 383.73 of this title.

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