NHTSA Study: Speed a Critical Factor in 5% of Crashes

The National Motor Vehicle Crash Causation Survey (short form here) is a landmark study. It’s first time the National Highway Transportation Safety Administration (NHTSA) has tackled the issue head-on (so to speak) in nearly 30 years. According to the final report, “traveling too fast” was the “critical pre-crash event” in only five percent of the 6,949 cases studied. In fact, in 12.2 percent of crashes, the vehicle was “stopped.” “Turning or crossing at intersection” was the number one critical pre-crash event (36 percent), followed by “Off the edge of the road” (22 percent). That said, NHTSA found “driving too fast for conditions” [NB: not necessarily over the speed limit] and “too fast for curve” were the number one and two “decision errors.” But top of the pile only means they accounted for 8.4 percent and 4.9 percent of “Critical Reasons for Pre-Crash Event Attributed to Drivers.” The major culprit after the jump.

Those of you who consider inadequate driver training and/or lax licensing a national tragedy have new ammunition. “About 41 percent of the driver-related critical reasons were recognition errors that include inattention, internal and external distractions, inadequate surveillance, etc. Of these, the most frequently occurring critical reason was inadequate surveillance that refers to a situation in which a driver failed to look, or looked but did not see, when it was essential to safely complete a vehicle maneuver.

“This critical reason was assigned to drivers in about 21 percent of crashes… About 33 percent of the driver-related critical reasons were decision errors that included too fast for conditions (8.4%), too fast for curve (4.9%), false assumption of others’ actions (4.5%), illegal maneuver (3.8%), and misjudgment of gap or others’ speed (3.2%). In about 10 percent of the crashes, the critical reason was a performance error, such as overcompensation (4.9%), poor directional control (4.7%), etc.”

Although vehicle-related causation table in the short form document was notable by its absence, vehicle manufacturers don’t get off Scott-free.

“The researchers, through their assessment of the vehicles, also assigned critical reasons to the vehicles. In such cases, failure of the tires/wheels was the most frequent vehicle-related critical reason followed by the failure of the braking system. The design and refinement of dashboard warning systems monitoring the status of critical vehicle elements such as the brake system, tire pressure, tread depth, etc., will benefit from such information.”