Frequency of Work Zone Accidents on Construction Projects

The overall objective of this research was to study work zone accidents in New York State, with particular attention to the occurrence and mitigation of rear-end vehicle accidents. The specific objectives were to:

• Recommend changes to the NYSDOT’s accident database system for more efficient management and analysis.
• Conduct a detailed investigation of rear-end crashes in work zones and recommend measures that can reduce the frequency of these types of crashes.
• Report on traffic exposure data and accident patterns / parameters to be incorporated into future NYSDOT accident data analysis.

Task 1 focused on evaluating the current NYSDOT work zone accident reporting system, surveying practices used in other states, and providing recommendations for improvement. The results of this task revealed that the current NYSDOT work zone accident reporting system is the most comprehensive in the country. Further changes to improve the system were recommended based on a review of the literature and practices being implemented in other state agencies.

The first part of Task 2 was focused on analyzing rear-end accidents in work zones that occurred in New York State between 1994 and 2001. Since data were available only on work zones that had accidents, truncated count data models were estimated to study the relationship between crash frequency and work zone characteristics. Ordered probit models were developed to study crash severity.

The second part of Task 2 provides some corrective actions to reduce frequency of work zone accidents. These actions are primarily based on a review of the literature since information on changes made by NYSDOT at the project level was not available to the research team.

The first subtask of Task 3 provided some recommendations to incorporate more project information to the work zone database either through adding more variables or including project information in a separate database that can be linked through a project identification number. The second subtask of Task 3 focused on various venues and approaches for obtaining exposure to traffic for various types of work zones. The final subtask of Task 3 focused on identifying parameters correlated with work zones and the county level.