When truck drivers were coached on unsafe behaviors or incidents within one week of the event, intervention was more impactful, according to a Virginia Tech Transportation Institute study on driver distraction.

Meanwhile, sporadic driver coaching was less effective in reducing the rate of critical safety events.

During a study presentation at the Fleet Safety Conference in California on Nov. 11, Susan Soccolich, research associate with VTTI’s Division of Freight, Transit and Heavy Vehicle Safety, shared results from a study of commercial motor vehicles that analyzed safety-critical incidences using video and sensor data.

The study reveals how drivers responded behaviorally to on-board monitoring systems and coaching after triggered events, such as cell phone use, drowsiness and other distractions.  

The study found that when introducing on-board monitoring systems in cabs, driver performance and safety increase in most cases. VTTI tracked seven fleets, including 116 vehicles and 354 drivers, to gather 3.8 million miles of data, and found:

• Fleet A decreased high severity safety event rates by 64% during intervention of an on-board monitoring or coaching system.

• Fleet H decreased high severity event rates by 37% during intervention.

After the nine-month trial with the monitoring system, VTTI withdrew the systems and tracked the results for two months. The fleets recorded lasting decreases in high-severity events, even after the system was removed.

• In the two months following removal of the coaching system, Fleet A continued to decrease high-severity event rates by 73%.

• Fleet H decreased high-severity event rates by 69% during withdrawal.

VTTI tracked drivers for one month to get a sense of their natural driving behavior (this is called the baseline), then introduced on-board monitoring system feedback and coaching for nine months.

The majority of events recorded by the on-board monitoring system were low-severity (about 95%). Of those incidents that were safety-critical events, many were caused by distraction (mostly eating food and drink-related.)

Distraction was recorded in 15% of Fleet A’s safety-critical events, and in 58% of Fleet H’s events.