Document Type

Technical Report

Publication Date



trafficc conflicts, crash-to-conflict ratios, intersections, conflict, observer training, expected values, yearly crash prediction, Florida-based conditions for conflicts


The new crash. reporting requirement. in Florida has significantl y reduced the number of crash reports available for roadway safet y s tud ies. Therefore, t he demand for accurate' crash surrogate·data ~As i ncreased. Addit;i.onally, the curtent method of est i mating crash surrogate data (Traffic Conflict Techniques f or Safety and Operations - ·'Engineers Guide, FHIIA-IP-88-026, Jan . 1989) is based on a National Hi ghway Institute study conducted i n 1982 in Kansas City. Missouri, for 48 intersections.

This report documents a comprehensive traffic conflict study conducted by CUTR to observe conflicts, collect crash data and develop new, simplified, expected value tables for Florida-based intersections and conditions. Thirteen traffic conflict types were surveyed from 178 intersections sampled from a five-county area in west-central Florida.

These tables can be used to estimate the expected annual number of different intersection types, and provide 90th and 95th percentile per day to evaluate relative safety problems at intersections.

Citation / Publisher Attribution

Development of Expected Value Conflict Tables for Florida-Based Traffic Crashes, Center for Urban Transportation Research, University of South Florida, 88 p.