First Hour of Driving the Most Dangerous

What is the most dangerous time of day to drive?  Accident statistics tell us that driving at night is dangerous, especially between the hours of midnight to 6 A.M. because of the prevalence of drowsy and alcohol-impaired drivers.  Driving during the morning and afternoon rush hours is also a dangerous time in congested areas.  A new study conducted by the Virginia Tech Transportation Institute (VTTI) now also points to the first hour of driving as the most dangerous for professional truck drivers.

The VTTI study examined accident risk relative to time spent driving, as a way to assess the safety impact of the current hours-of-service rules.  Study results showed a significant spike in the rate of critical incidents during the first hour of driving.  In comparison, there was no statistical difference in the critical incident rate between the 2nd and 11th hours of driving.  The study notes that these findings correspond with other study results, such as the Federal Motor Carrier Safety Administration’s Large Truck Crash Causation Study.

The reasons for the first-hour spike in critical incidents were not determined.  However, the study authors hypothesize that sleep inertia might be one factor, a condition where drivers may not be fully alert immediately after awaking from sleep.  The increase in complex driving situations that drivers experience during the first hour of driving (i.e. heavy traffic) was also cited as a possible cause.