The following terms are used in this note :

Accident   An incident reported to the Police, involving personal injury occurring on roads in the Territory, in which one or more vehicles are involved.
Casualty   A person killed or injured in an accident in which there may be more than one casualty.
Fatal accident  

Traffic accident in which one or more persons dies within 30 days of the accident.
Serious accident   Traffic accident in which one or more persons injured and detained in hospital for more than twelve hours.
Slight accident   Traffic accident in which all persons involved are either not detained in hospitals or detained for not more than twelve hours.
Killed casualty Sustained injury causing death within 30 days of the accident.
Serious injury   An injury for which a person is detained in hospital as an 'in-patient' for more than twelve hours.  Injuries causing death 30 or more days after the accident are also included in this category.
Slight injury   An injury of a minor character such as a sprain, bruise or cut not judged to be severe, or slight shock requiring roadside attention and detention in hospital is less than 12 hours, or not required.
Road users   Pedestrians and vehicle users which include all occupants (i.e. driver or rider and passengers, including persons injured while boarding or alighting from the vehicle).
Vehicles involved   Vehicles whose drivers or passengers are injured, which hit a pedestrian or another vehicle whose driver or passengers are injured, or which contribute to the accident.