Relationship between Infrastructure, Driver Error, and Critical Incidents

During the course of a Federal Highway Administration (FHWA)-sponsored research project ”Identification of Driver Errors,” ”driver errors” in crashes and near-crashes (i.e., critical incidents) were investigated and an analysis approach was developed to help identify infrastructure-related and non-infrastructure-related problems at intersections and other roadway sites. The research team carefully examined the relationship between the infrastructure, driver error, and critical incidents. This was accomplished by first determining which incidents appeared to have an infrastructure component (signing, signaling, delineation, alinement, geometry, etc.). These incidents were then reexamined to determine the precise nature of the infrastructure components. Once the problems had been identified, countermeasures were suggested. This work is a demonstration of the synergistic effects of combining human factors engineering techniques with traffic engineering. By broadening the earlier traffic-conflict technique to include greater consideration of driver behavior, with emphasis on generalized driver errors, a better understanding of critical incidents and their corresponding countermeasures has been obtained.