The Connecticut Department of Transportation (ConnDOT) uses historical accident data as an important component in its ongoing evaluation of Connecticut’s public highways, streets and roads. Accident data plays an integral part in ConnDOT’s responsibilities for maintaining the state highway system, and is a key factor in the decision making process for roadway improvements and modifications. ConnDOT’s Office of Environmental Planning uses accident data as an important tool in their analysis of state roads; it is often a primary component of the purpose and need for environmental documents. Planning for roadway modifications includes reviewing available accident records, and analyzing accident frequencies and trends to determine if a modification of the roadway would improve safety.
The Accident Records and Statistics Section of the Office of Inventory and Forecasting is responsible for the codification, maintenance and compilation of motor vehicle traffic accident data. Section 14-108a of the Connecticut Motor Vehicle Laws, Title 14, requires any police officer, agency or individual that investigates a reportable motor vehicle accident to forward one copy of the police accident report to ConnDOT upon completion of the investigation. A reportable motor vehicle accident is defined as one in which any person is killed or injured or in which damage to the property of any one individual in excess of one thousand dollars is sustained. ACCIDENT RECORDS PRODUCTS The following is a brief overview of some of the major accident reports and summaries that are produced by the Accident Records and Statistics Section:
    • Traffic Accident Surveillance Report (TASR). This report, which is produced for the latest 3-year period available, shows accident totals, traffic counts, accident rates and various roadway features for the entire state highway system. For each state road location, TASR displays location characteristics, accident totals, number of vehicles passing through the location, million vehicle miles of travel, average accident rate for that type of location, actual accident rate for that location, critical accident rate for that location, and the ratio of the actual accident rate to the critical accident rate. TASR is sorted by route and cumulative mileage.
    • Suggested List of Surveillance Study Sites (SLOSSS). This is a list of TASR locations that experienced abnormally high accident rates for the corresponding 3-year period. Each TASR location with 15 or more accidents and whose actual accident rate is greater than its critical accident rate is included on SLOSSS. SLOSSS displays similar information to TASR, with the addition of a sequence number that is used to rank the locations by the ratio of the actual accident rate to the critical accident rate. SLOSSS is sorted both by route and cumulative mileage and also by sequence number. The objective in developing SLOSSS is to define those locations which have the greatest promise of accident reduction and thus to give a broad measure of overall needs of highway safety improvements.
    • Q-Factors. This is a report that displays injury and fatal accident cost factors by roadway group and intersection types for state roads. Q-Factors, which is produced for a 3-year period, displays fatal accidents, injury accidents, property damage only accidents, fatalities, injuries, accident totals, and cost factors derived from injury and fatality costs reported annually by the National Safety Council.
    • Before and After Studies. In conjunction with the Annual Safety Report prepared by the ConnDOT Division of Traffic Engineering, Before and After Studies of accident frequencies are periodically performed on safety improvement projects to evaluate their cost effectiveness. The Annual Safety Report is annually submitted to the Federal Highway Administration (FHWA).
    • Accident Experience. This is a history of accidents for a specific location and time period, which describes the dynamics of each accident in detail. These are prepared daily for various sources.
    • Connecticut Accident Summary Tables (CAST). These tables distribute accident, vehicle and person totals by major fields that are contained in the ConnDOT database file. They can be produced for any type of accident as well as for all accidents on file.
    • Connecticut Traffic Accident Facts. This report, which is published biennially, presents data concerning motor vehicle traffic accidents that occurred on Connecticut’s publicly maintained roadways for a particular year. The report uses text, tables, graphs, comments and pictures to present the data. The Connecticut Traffic Accident Facts report is distributed to various organizations upon its publication.
The Accident Records and Statistics Section is also responsible for the Fatality Analysis Reporting System (FARS) program, which is a federal program that requires the collection of data on fatal motor vehicle traffic accidents. The National Highway Traffic Safety Administration (NHTSA) funds a cooperative agreement with ConnDOT for the purpose of data acquisition for FARS. FARS data is entered into a designated computer and transmitted to NHTSA nightly.
October 1998
Connecticut Department of Transportation
Office of Inventory and Forecasting
2800 Berlin Turnpike
P.O. Box 317546
Newington, CT. 06131-7546