3. Data on Traffic Accidents.
Traffic accident prevention programs are continuous studies of accidents, violations, vehicle
registrations, and the remedial actions taken. These programs are never completed. The study of
these records assists :in--
o Identifying high accident rate locations and taking corrective action.
o Planning remedial actions and selective enforcement programs.
o Evaluating the above actions and their effectiveness. This is done through before and after
We will discuss how the data is organized and transformed into useful information. Later, we see how
the information is used. Keep in mind that the following discussion applies equally to the analysis of
traffic citation data. The principles are the same.
a. There are six basic steps in the study of accidents at a location:
Obtain sufficient accident data.
Select high accident rate locations.
Prepare collision and condition diagrams.
Make field observations at the location.
Analyze facts and field data and recommend corrective actions.
b. Obtain Sufficient Accident Data
The validity of any analysis depends on the accuracy of the raw information from which it is obtained.
This is particularly important when studying the causes of accidents. Accidents occur as a result of a
variety of factors in complex combinations. Some of the factors are the location, time, and cause of the
c. Select High Accident Rate Locations
One of the most significant factors, is the location of each accident: . If you know where the accidents
are happening, you can apply selective enforcement of traffic laws in that area. You can also adjust
your patrol areas to provide more intensive coverage.
There are two methods of storing and retrieving accident location data: by accident location file and by
The accident location file uses the location of the accident as the basis of order. A record is maintained
for each intersection and for each area between intersections. Reports are then filed chronologically for
each site. See Figure 2-1.