Glossary of Terms

These definitions are used in the traffic safety community and have been compiled from various NHTSA, LADOTD, and government publications, including ANSI D16.1996 and AAMVA ANSI D20-2003 technical manuals. They provide explanation to some of the terminology used throughout the site and CRASH reports.


NHTSA defines a crash as alcohol-related if either a driver or a non-motorist (usually a pedestrian) had a measurable or estimated blood alcohol concentration (BAC) of 0.01 grams per deciliter (g/dl) or above. Some states in the State Data System also report a crash as alcohol-related if the Police Accident Report (PAR) indicates evidence of alcohol being present, even though the crash participant may not have been tested for alcohol.


Blood Alcohol Concentration. BAC is measured as a percentage by weight of alcohol in the blood (grams/deciliter). A positive BAC level (0.01 g/dl and higher) indicates that alcohol was consumed by the person tested.


Large motor vehicles generally used to carry more than 10 passengers, including school buses, inter-city buses, and transit buses.


An avalanche, cloudburst, cyclone, earthquake, flood, hurricane, landslide, lightning, tidal wave, tornado, torrential rain, or volcanic eruption.


The category which best describes the general type of collision which was the first event.


A crash involving a commercial motor vehicle.

The MCMIS Crash data includes crashes that are reported by states to the FMCSA through the SAFETYNET computer reporting system. The Crash File includes the National Governors' Association (NGA) recommended data elements collected on trucks and buses involved in crashes that meet the NGA recommended crash threshold. An NGA reportable crash must involve a truck (a vehicle designed, used, or maintained primarily for carrying property, with a gross vehicle weight rating or gross combination weight rating of more than 10,000 lbs.) or bus (a vehicle with seats for at least nine people, including the driver) or a vehicle carrying hazardous material. The crash must result in at least one fatality; one injury where the person injured is taken to a medical facility for immediate medical attention; or one vehicle having been towed from the scene as a result of disabling damage suffered in the crash. The Crash Profile Reports use the MCMIS Crash data as of March 2007.


An event which produces injury and/or property damage, involves a motor vehicle in transport, and occurs on a trafficway or while the vehicle is still in motion after running off the trafficway.


An unintended event that causes a death, injury or damage and involves a MOTOR VEHICLE on a TRAFFICWAY. (This includes only traffic crashes which have resulted in a DEATH or INJURY to one or more persons. CRASHES which have caused only vehicle or property damage are not included.)


  • Fatal Crash: A police-reported crash involving a motor vehicle in transport on a trafficway in which at least one person dies.
  • Injury Crash: A police-reported crash involving a motor vehicle in transport on a trafficway in which no one died but at least one person was reported to have either an incapacitating injury, a visible but not incapacitating injury, or a possible injury with no visible evidence.
  • Property-Damage-Only (PDO) Crash: A police-reported crash involving a motor vehicle in transport on a trafficway in which no one involved in the crash was killed or injured, but enough damage occurred to one or more vehicles to meet the state's minimum inclusion criteria.

Child Occupant Seatbelt Law (Child passenger restraint system) § R.S. 32:295

Except as provided in Subsections C, D, and E of this Section, every driver in this state who transports a child or children under the age of eighteen years in a motor vehicle that is in motion and is required by federal safety standards to be equipped with a safety belt system or lower anchors and tethers for children in a passenger seating position shall have the child properly restrained according to the vehicle and child safety seat manufacturer's instructions, as follows:

(1) A child who is younger than the age of two years shall be restrained in a rear-facing child restraint system that complies with all applicable federal regulations until the child reaches the weight or height limit of the child restraint system as set by the manufacturer.

(2) A child who is at least two years of age or older and has reached the rear-facing weight or height limits of the child restraint system as set by the manufacturer, shall be restrained in a forward-facing child restraint system with an internal harness until the child reaches the weight or height limit of the child restraint system set by the manufacturer.

(3) A child who is at least four years of age and has outgrown the forward-facing weight or height limits of the child restraint system as set by the manufacturer shall be restrained in a belt-positioning child booster seat, secured with a vehicle lap-shoulder seat belt, according to the manufacturer's instructions.

(4) A child who is at least nine years of age or has outgrown the height or weight limits of a child restraint system or belt-positioning child booster seat as set by the manufacturer shall be restrained with the motor vehicle's adult safety belt adjusted and fastened around the child's body to fit correctly. The adult safety belt fits correctly when the child sits all the way back against the vehicle seat, the child's knees bend over the edge of the vehicle seat, the belt fits snugly across the child's thighs and lower hips, and not the child's abdomen, and when the shoulder strap snugly crosses the center of the child's chest and not the child's neck.

(5) A child who is younger than thirteen years of age shall be transported in the rear seat of a motor vehicle, when available, in a properly used child restraint system, belt-positioning child booster seat, or adult safety belt that complies with all applicable federal regulations.

(6) A child who because of age or weight can be placed in more than one category shall be placed in the more protective category.

Click here to see the full statute.


Time period from 0600 (6:00 A.M.) to 1759 (5:59 P.M.)


A fatal injury is any injury that results in death within 30 days after the motor vehicle crash in which the injury occurred. If the person did not die at the scene but died within 30 days of the motor vehicle crash in which the injury occurred, the injury classification should be changed from the attribute assigned to the attribute "Fatal Injury."


It is unlawful...

  • for any person to drink, consume, or be in possession of an alcoholic beverage while operating, or while riding as a passenger in, any private motor vehicle when such vehicle is upon a public road
  • for any operator or passenger of any motor vehicle to drink, consume, or be in possession of any bottle, container or receptacle containing alcoholic beverages which has been opened or the seal of a licensed manufacturer has been broken, or the contents of which have been exposed to the air, except when such bottle, receptacle, or container shall be kept in the trunk of the motor vehicle, or kept in some other area of the vehicle not normally occupied by the driver or passengers in the event that the motor vehicle is not equipped with a trunk. On a first conviction, punishable by fines up to $125 and imprisonment for 10 days to 6 months.

Click here to see the full statute.


A driver is an occupant who is in actual physical control of a motor vehicle or, for an out-of-control motor vehicle, an occupant who was in control until control was lost.

This does NOT include a bicyclist.


  • Young Driver: 15-24 (bicyclists not included)
  • Older Driver: 65 and above


The description of the condition of the driver at the time of the crash and that is relevant to the crash. Investigating officers may select up to 2 conditions that applied to the driver at the time of the crash in this field.



Discovery and Admission Law (Discovery and Admission as Evidence of Certain Reports and Surveys) § 407

Notwithstanding any other provision of law, reports, surveys, schedules, lists, or data compiled or collected for the purpose of identifying, evaluating, or planning the safety enhancement of potential accident sites, hazardous roadway conditions, or railway-highway crossings, pursuant to sections 130, 144, and 148 of this title or for the purpose of developing any highway safety construction improvement project which may be implemented utilizing Federal-aid highway funds shall not be subject to discovery or admitted into evidence in a Federal or State court proceeding or considered for other purposes in any action for damages arising from any occurrence at a location mentioned or addressed in such reports, surveys, schedules, lists, or data.

Click here to see the full statute.


Any traffic accident occurring on an interstate which is not level with the adjacent ground.


Fatal Analysis Reporting System, a data system created by the United States Department of Transportation (DOT) and the National Highway Traffic Safety Administration (NHTSA) in 1975 to assist the traffic safety community in identifying traffic safety problems and evaluating both motor vehicle safety standards and highway safety initiatives.

You can find more information here.


A crash that results in at least one person fatally injured.


The CRASHES in which there was an INJURY or a DEATH.


The value specified by the manufacturer as the recommended maximum loaded weight of a single motor vehicle. This rating includes the maximum rated capcity of a vehicle, including the base vehicle, mounted equipment, and any cargo and passengers. Most of the time, the GVWR is the sum of the maximum rated capacity of the axles of the vehicle.


The term “IN TRANSPORT” denotes the state or condition of a transport vehicle which is in motion or within the portion of a transport way ordinarily used by similar transport vehicles. When applied to MOTOR VEHICLES, “in transport” means in motion or on a roadway.


  • MOTOR VEHICLE in traffic on a highway
  • Driverless MOTOR VEHICLE in motion
  • Motionless MOTOR VEHICLE abandoned on a roadway
  • Disabled MOTOR VEHICLE on a roadway
  • And others

In roadway lanes used for travel during rush hours and parking during off-peak periods, a parked MOTOR VEHICLE is in transport during periods when parking is forbidden.


Bodily harm to a person as a result of a CRASH. INJURIES do not include DEATHS.


The police-reported injury severity of a person involved in a crash:

  • Fatal Injury
  • Suspected Injury (Suspected Serious Injury, Suspected Minor Injury, Possible Injury)
  • No Apparent Injury


An area which contains a crossing or connection of two or more roadways not classified as driveway access, either along a roadway within an intersection proper or within 50 feet of an intersection.


A crash occurring at an intersection as reported by the investigating officer's location information.


A DEATH as a result of a CRASH.


Trucks with over 10,000 pounds Gross Vehicle Weight Rating (GVWR), including single unit trucks and truck tractors.


A person who is licensed by a state to operate a MOTOR VEHICLE on public roadways.


Trucks with 10,000 pounds Gross Vehicle Weight Rating (GVWR) or less, including pickups, vans, and sport utility vehicles (SUV).


Where the CRASH occurred (business, residential, etc.)


A traffic record with some fields of the crash report not filled out.


Any motorized (mechanically or electrically powered) road vehicle not operated on rails. When applies to motor vehicles, "in transport" refers to being in motion OR on a roadway.


A two- or three-wheeled motor vehicle (e.g., motor scooters, mini-bikes, and mopeds).


Time period from 1800 (6:00 P.M.) to 0559 (5:59 A.M.)


An area along the roadway (including the shoulder) that does not contain a crossing or connection of two or more roadways, and is greater than 50 feet from an intersection.


A person who is in or on a VEHICLE including the driver.


The crime of operating a vehicle while intoxicated is the operating of any motor vehicle, aircraft, watercraft, vessel, or other means of conveyance when the operator is under the influence of alcoholic beverages or the operator's BAC is 0.08% or more. On the first offense, punishable by a fine of $300 to $1,000, and 10 days to 6 months imprisonment (exceptions are in place). If the offender has a blood alcohol concentration of 0.20% or more, the violation is punishable with fines of $750 to $1,000 without benefit of parole, probation, or suspension of sentence, and suspension of driver's license for 2 years.

Click here to see the full statute.


An object in the roadway which is not part of the roadway (such as rocks, fallen trees, debris)


Any crash in which a vehicle rotates 90 degrees or more about any true longitudinal or lateral axis.


Police Accident Report. A report completed by police officers at a motor vehicle traffic crash scene. It contains information describing characteristics of the crash, the vehicles, and people involved. The report also includes the results of the officer’s investigation about the crash itself.


An occupant of a motor vehicle other than the driver.


A non-motorized VEHICLE propelled by pedaling such as a bicycle, tricycle, unicycle, or pedal car. (The PEDALCYCLE is counted as a VEHICLE and the OCCUPANTS are counted as DRIVERS and PASSENGERS.)


Person Type (i.e., the type of person involved in a crash): A person who is not an occupant of a motor vehicle in transport or a bicyclist.

Crash Category: a crash involving a person traveling on foot.


A crash involving at least one driver or motorcyclist who is predicted to have a blood alcohol content (BAC) greater or equal to 0.02%.

A Louisiana-specific regression equitation is used to predict alcohol BAC when BAC is pending or unknown.


Includes all submits and refusals which did not lead to either a DWI conviction or an application of the 894 law.


The main cause of a CRASH.


A crash that results in damage to the motor vehicle or other property, but without injury to any occupants or non-motorists. No apparent injury is a situation where there is no reason to believe that the person received any bodily harm from the motor vehicle crash. There is no physical evidence of injury and the person does not report any change in normal function.

Primary Seatbelt Law (Safety belt use; tags indicating exemption) § R.S. 32:295.1

Each driver of a passenger car, van, sports utility vehicle, or truck having a gross weight of twenty-six thousand pounds or less in this state shall have a safety belt properly fastened about his or her body at all times when the vehicle is in forward motion. The provisions of this Section shall not apply to those cars, vans, sports utility vehicles, or pickups manufactured prior to January 1, 1981. Click here to see the full statute.


A rate is computed by dividing a total count by population statistics such as VMT, number of licensed drivers, or population.


When a law enforcement officer places a person under arrest for operating a motor vehicle while intoxicated and the person refuses to submit to an approved chemical test for intoxication.

Click here to see the full statute and a more detailed explanation.


All areas that are un-incorporated and incorporated areas with less than 2,500 population except for Jefferson Parish which is considered all URBAN.


When a law enforcement officer places a person under arrest for operating a motor vehicle while intoxicated and the person submits to an approved chemical test for intoxication and such test results show blood alcohol content over the legal limits.

Go here for a more detailed explanation.


Any land way open to the public as a matter of right or custom for moving persons or property from one place to another. This does not include land ways which are under construction or closed and which have been marked by signs or barriers.


A TRANSPORT VEHICLE consists of one or more devices or animals and their load. Such devices or animals must include at least one of the following:

  • A transport device, or a unit made up of connected transport devices, while idle or in use for moving persons or property from one place to another
  • An animal or team of animals while in use for moving persons or property other than the animal or team itself from one place to another
  • A movable device such as construction, farm, or industrial machinery outside the confines of a building and its premises while in use for moving persons, the device itself, or other property from one place to another

If such a device or animal has a load, the load is part of that TRANSPORT VEHICLE. Loads include:

  • Persons or property upon, or set in motion by, the device or animal
  • Persons boarding or alighting from the device or animal
  • Persons or property attached to and in position to move with the device


A motor vehicle consisting of a TRUCK TRACTOR which has a trailer or semi-trailer attached.


A motor vehicle designed and used primarily for drawing other vehicles and not so constructed as to carry a load other than a part of the weight of the vehicle and load drawn. When connected to a trailer or semi-trailer, such a device is considered a TRUCK COMBINATION.




Any incorporated area with more than 2,500 population and all of Jefferson Parish.


A device for carrying or transporting persons or things, i.e., cars, trucks, farm equipment, buses, motorcycles, pedalcycles, trains, and recreational vehicles.


The category which best describes the DRIVER'S infringement of MOTOR VEHICLE traffic laws.


Vehicle Miles Traveled is an estimate of the miles traveled by all motor vehicles traveling on Louisiana roads. VMT is obtained by combining two estimates of (1) VMT of interstates and state roads and (2) VMT of local roads. The estimate of interstates and state roads are obtained from daily vehicle miles travel estimates. The daily vehicle miles traveled is obtained by dividing the state roads and interstates in control sections. Counters on these control sections count daily travel. These counts are then multiplied by the miles of the control sections.

Note: All population statistics show an increase. However, the VMT exhibits much more variation over time than expected from the variation in licensed drivers and population. Part of the variation may be due to estimation.


Time period from 0600 (6:00 A.M.) Monday to 1759 (5:59 P.M.) Friday


Time period from 1800 (6:00 P.M.) Friday to 0559 (5:59 A.M.) Monday