Bituminous Insurance Companies

Critical Incidents Highest During First Hour of Driving

A recent study completed for the Federal Motor Carrier Safety Administration (FMCSA) by the Virginia Tech Transportation Institute (VTTI), entitled Analysis of Risk as a Function of Driving-Hours 1 to 11, indicated a much higher number of critical incidents during the first hour of driving. The report is currently under peer review and preliminary results were presented during a Webinar sponsored by the FMCSA.

While the main issue addressed in the study was the effect of the increase in the Federal Motor Carrier Safety Regulations' (FMCSR) hours-of-service regulations to allow 11-hours of driving time, versus the previous 10-hour limit, the increase in risk during the first hour of driving was evident.

The data was collected using highly-instrumented vehicles during their normal, revenue producing runs. Both line-haul and long-haul operations were studied. Data was collected during 2.3 million miles of driving and 190,000 hours of operation.

The study defined "critical incidents" as crashes, near-crashes (hard braking or steering), and crash-relevant conflicts (less severe evasive maneuver as compared to near-crashes).

The first hour of driving indicated a 100 percent increase in critical incidents over nearly all other times of driving. The 11th hour of driving showed no increase in critical incidents.

Another interesting result of the study indicated a bell-curve increase in critical incidents from morning rush-hour to noon and then declining to evening rush-hour.

COPYRIGHT ©2008, ISO Services Properties, Inc.

The information contained in this publication was obtained from sources believed to be reliable. ISO Services Properties, Inc., its companies and employees make no guarantee of results and assume no liability in connection with either the information herein contained or the safety suggestions herein made. Moreover, it cannot be assumed that every acceptable safety procedure is contained herein or that abnormal or unusual circumstances may not warrant or require further or additional procedure.