Link to QCS Corp. Home Page.
Quality Control Systems Corporation
In business since 1987 – thanks to our clients, customers, friends, and families

An Unusual Cluster of Fatal Rollover Crashes
on I-5 in Fresno County, California


Rollover crash vehicle.


An Unusual Cluster of Fatal Rollover Crashes on I-5 in Fresno County, California.

We have identified an unusual group of 58 fatal crashes along a sixty-six mile stretch of Interstate 5 (I-5, also known as the Westside Freeway) in Fresno County, California. All of these crashes involved rollovers that occurred as the first harmful event of the crash. These crashes occurred north of Avenal on I-5, running north to West Nees Avenue west of Firebaugh. The posted roadway speed limit where these crashes occurred was 70 miles per hour. Seventy-four persons were killed in these crashes over a seven year period from 2002 through 2008.

Both the number of such crashes as well as the proportion of fatal crashes on this roadway involving first-event rollovers make this cluster noteworthy. The rate of first-event rollovers per crash was more than 2.5 times higher than for other segments of interstate highways in the United States with the same 70 miles per hour speed limit at the time of our study.

With four exceptions, all of the crashes were single vehicle crashes, not involving any pedestrians. The sequence of events is known for 39 of the vehicles in these crashes; of these, 30 involved roadway departures. Tire failures were reported in 15 of these vehicles.

This unusual cluster of fatal crashes was identified using data from the Fatality Analysis Reporting System (FARS) maintained by NHTSA and a statistical criterion based on the Poisson distribution that tests the likelihood of an expected number of events, given the number of events that actually occurred. This technique is related to one described in the paper: "Improving Surveillance for Injuries Associated with Potential Motor Vehicle Safety Defects." Injury Prevention, April 2004, 10:88-92, by R.A. Whitfield and Alice K. Whitfield.

If you would like further information, please to send us an email.

(Link to our Crash Mapping page.)

Link to:

QCS Corp. Home Page

Our Research

Our Press Clippings

How to Contact Us


Terms of Use and Disclaimers     Privacy

Copyright © Quality Control Systems Corp. All rights reserved.