Factors influencing injury severity to highway workers in work zone intrusion accidents

Highway workers in work zones are in close proximity to traveling vehicles, exposing them to injury risks when vehicles intrude into the work zone. The purpose of this research was to perform an analysis of injuries endured by highway workers due to intrusion accidents and to identify factors that would have a significant effect on injury severity.

Ten years of California work zone injury data were collected and analyzed. The data were first used to determine trends in work zone injury. Statistical models were also created to evaluate variables influencing injury severity. Statistical models included multiple correspondence analysis, Cox proportional hazard regression, logistic regression, and Poisson regression.

Statistical analysis of California injury data identified the 4 variables of accident/work zone location, work zone duration, time of day, and type of activity performed by the worker as having the most significant impact on injury severity. The results show that locations such as those on freeways/highways and stationary lane closures result in more severe injuries than work zones on city streets. Short-term stationary and short-duration work zones had increased odds of nonminor injuries compared to mobile work zones. For the time of day, the results indicate that the odds of more serious injuries are higher during nonpeak hours than during peak rush hours. Finally, workers on foot have greater odds of experiencing a more severe injury versus workers inside vehicles.

This research has shown that considering the effects of work zone location, duration, time of day, and worker activity can have the most significant impact on risk of injury to workers. Understanding these factors can provide a basis for planning and design of work zones to improve worker safety.