Glossary of Frequently Used Terms

The number of crashes involving at least one motor carrier that had a valid US DOT number that were used to match the carrier with a record in the census file at the time of the crash and at least one motor carriers that did not have a valid US DOT number at the time of the crash.

Any motor vehicle designed primarily to transport nine or more persons, including the driver.

A structure or fixture designed to contain, or support, the material or property to be transported on the vehicle.

Bulk packaging that: (1) Is a tank intended primarily for the carriage of liquids or gases and includes appurtenances, reinforcements, fittings, and closures (for the definition of a tank, see 49 CFR 178.320, 178.337–1, or 178.338–1, as applicable); (2) Is permanently attached to or forms a part of a motor vehicle, or is not permanently attached to a motor vehicle but which, by reason of its size, construction or attachment to a motor vehicle is loaded or unloaded without being removed from the motor vehicle; and (3) Is not fabricated under a specification for cylinders, intermediate bulk containers, multi-unit tank car tanks, portable tanks, or tank cars.

A driver holding a CDL.

The load-supporting frame of a commercial motor vehicle, exclusive of any appurtenances which might be added to accommodate cargo.

Any combination of vehicles with a gross combined weight of 26,001 pounds or more, with trailer(s) weighing 10,000 pounds or more.

Any single vehicle having a gross weight of 26,001 pounds or more, or any such vehicle towing another weighing 10,000 pounds or less.

Any vehicle or combination of vehicles not meeting the definition of Class A or Class B, designed to transport 16 or more passengers (including the driver), or any vehicle required by federal regulations to be placarded to carry hazardous material.

A license type defined by states, which is not part of the FMCSA standards. Some states use it to classify regular, passenger car drivers licenses, while others use it to classify specific weights or types of vehicles. The definition varies from state-to-state.

A license type denoting that the driver can only operate Class B and C passenger vehicle or school buses.

A type of driver's license required to operate large or heavy vehicles. Requires a higher level of knowledge, experience, skills, and physical abilities than that required to drive a non-commercial vehicle. CDL holders are held to a higher standard when operating any type of vehicle on public roads.

A motor vehicle or combination of motor vehicles used in commerce to transport passengers or property. See 49 CFR 383.5 and 49 CFR 390.5.

A liquid or solid that causes irreversible damage to human skin at the site of contact within a specified period of time. A liquid, or a solid which may become liquid during transportation, that has a severe corrosion rate on steel or aluminum based on the criteria in § 173.137(c)(2) is also a corrosive material.

An occurrence involving a commercial motor vehicle in interstate or intrastate commerce in which: A vehicle was towed from the scene; A fatality occurred; or A person was injured and required immediate medical treatment away from the crash scene.

Headquarters location of a motor carrier.

Any person who operates any commercial motor vehicle.

A crash involving any vehicle (truck, bus, car, etc.) resulting in death within 30 days of the crash as a result of an injury sustained.

This census of fatal motor vehicle crashes with a set of data files documents all qualifying fatalities that occurred within the 50 States, the District of Columbia, and Puerto Rico since 1975. To qualify as a FARS case, the crash had to involve a motor vehicle traveling on a trafficway customarily open to the public, and must have resulted in the death of a motorist or a non-motorist within 30 days of the crash.

A liquid having a flash point of not more than 60 °C (140 °F), or any material in a liquid phase with a flash point at or above 37.8 °C (100 °F) that is intentionally heated and offered for transportation or transported at or above its flash point in a bulk packaging, with the following exceptions: (1) Any liquid meeting one of the definitions specified in § 173.115. (2) Any mixture having one or more components with a flash point of 60 °C (140 °F) or higher, that make up at least 99 percent of the total volume of the mixture, if the mixture is not offered for transportation or transported at or above its flash point. (3) Any liquid with a flash point greater than 35 °C (95 °F) that does not sustain combustion according to ASTM D 4206 (IBR, see § 171.7 of this subchapter) or the procedure in appendix H of this part. (4) Any liquid with a flash point greater than 35 °C (95 °F) and with a fire point greater than 100 °C (212 °F) according to ISO 2592 (IBR, see § 171.7 of this subchapter). (5) Any liquid with a flash point greater than 35 °C (95 °F) which is in a water-miscible solution with a water content of more than 90 percent by mass.

Desensitized explosives that— 1.When dry are Explosives of Class 1 other than those of compatibility group A, which are wetted with sufficient water, alcohol, or plasticizer to suppress explosive properties; and 2.Are specifically authorized by name either in the Hazardous Materials Table in § 172.101 of this subchapter or have been assigned a shipping name and hazard class by the Associate Administrator under the provisions of— a) A special permit issued under subchapter A of this chapter; or b)An approval issued under § 173.56(i). 3.Readily combustible solids are materials that— a)Are solids which may cause a fire through friction, such as matches; b)Show a burning rate faster than 2.2 mm (0.087 inches) per second when tested in accordance with the UN Manual of Tests and Criteria (IBR, see § 171.7 of this subchapter); or c)Any metal powders that can be ignited and react over the whole length of a sample in 10 minutes or less, when tested in accordance with the UN Manual of Tests and Criteria. 4.Polymerizing materials are materials which, without stabilization, are liable to undergo an exothermic reaction resulting in the formation of larger molecules or resulting in the formation of polymers under conditions normally encountered in transport.

A group of heavy duty trucks that is operated by a single business entity for the transport of goods and groups of people, or services that require more vehicular power.

This catalog maintains the Motor Carrier Management Information System (MCMIS). MCMIS contains information on the safety fitness of commercial motor carriers (truck & bus) and hazardous material (HM) shippers subject to the Federal Motor Carrier Safety Regulations (FMCSR) and the Hazardous Materials Regulations (HMR).

Any solid waste (including garbage, trash, and sanitary waste from septic tanks) derived from households (including single and multiple residences, hotels and motels, bunkhouses, ranger stations, crew quarters, campgrounds, picnic grounds, and day-use recreation areas). This term is not applicable to consolidated shipments of household hazardous materials transported from collection centers. A collection center is a central location where household waste is collected.

A material which has a vapor pressure greater than 300 kPa (43.5 psia) at 50 °C (122 °F) or is completely gaseous at 20 °C (68 °F) at a standard pressure of 101.3 kPa (14.7 psia).

1. A value specified by the manufacturer of the power unit, if such value is displayed on the Federal Motor Vehicle Safety Standard (FMVSS) certification label required by the National Highway Traffic Safety Administration, OR 2. The sum of the gross vehicle weight ratings (GVWRs) or the gross vehicle weights (GVWs) of the power unit and the towed unit(s), or any combination thereof, that produces the highest value. Exception: The GCWR of the power unit will not be used to define a commercial motor vehicle when the power unit is not towing another vehicle.

The prescribed weight limit from the vehicle manufacturer, indicating the total amount the vehicle can weigh to operate safely.

A substance or material which has been determined by the Secretary of Transportation to be capable of posing an unreasonable risk to health, safety, and property when transported in commerce, and which has been so designated.

Materials designated by the Secretary of the Department of Transportation as posing an unreasonable threat to the public and the environment.

Any person(s) injured as a result of the crash who immediately receives medical treatment away from the crash scene.

A motor carrier engaged in transportation of any amount of hazardous material across State lines, including international boundaries; or (2) within one State as part of a through movement that originates or terminates in another State or country.

A motor carrier engaged in transportation of passengers or property across State lines, including international boundaries; or (2) within one State as part of a through movement that originates or terminates in another State or country.

A motor carrier engaged in transportation of passengers or property entirely within one State that is not part of a through movement that originates or terminates in another State or country.

Includes all trucks used for commercial purposes with a gross vehicle weight rating (GVWR) or gross combination weight rating (GCWR) greater than 10,000 pounds, any motor vehicle designed to transport nine or more people, including the driver, or any vehicle displaying a hazardous materials placard.

The number of crashes involving only motor carriers that had a valid US DOT numbers that were used to match the carrier with a record in the census file at the time of the crash.

An FMCSA system that contains crash, census, and inspection files created to monitor and develop safety standards for commercial motor vehicles operating in interstate commerce.

Includes a vehicle, machine, tractor, trailer, or semitrailer, or any combination thereof, propelled or drawn by mechanical power and used upon the highways in the transportation of passengers or property. It does not include a vehicle, locomotive, or car operated exclusively on a rail or rails, or a trolley bus operated by electric power derived from a fixed overhead wire, furnishing local passenger transportation similar to street-railway service.

The number of crashes involving only motor carriers that did not have valid US DOT numbers at the time of the crash.

A material that may, generally by yielding oxygen, cause or enhance the combustion of other materials.

A material which is known to be so toxic or infectious to humans as to afford a hazard to health during transportation.

Any motor vehicle which is designed to be drawn by another motor vehicle and attached to the towing motor vehicle by means of a “reach” or “pole,” or by being “boomed” or otherwise secured to the towing motor vehicle, for transporting long or irregularly shaped loads such as poles, pipes, or structural members, which generally are capable of sustaining themselves as beams between the supporting connections.

A material that contains unstable isotopes of an element undergoing decay and emitting radiation.

A crash is reported to FMCSA if it involves a truck, bus or any vehicle displaying a hazardous materials placard AND that vehicle is involved in a crash while operating on a roadway customarily open to the public, which results in a fatality, an injury or a towaway.

Any motor vehicle (truck, bus, car, etc.) disabled as a result of the crash and transported away from the scene by a tow truck or other vehicle.

Any self-propelled commercial motor vehicle except a truck tractor, designed and/or used for the transportation of property with a gross vehicle weight rating (GVWR) greater than 10,000 pounds.

An area of a trafficway with highway construction, maintenance, or utility-work activities. A work zone is typically marked by signs, channeling devices, barriers, pavement markings, and/or work vehicles.