WASHINGTON, D. C. –In a study to determine the safety of driving a truck over a period of one to 11 hours, it was revealed that the first hour is the most dangerous -by far.

The higher crash percentage in the first hour of driving is a major finding that is relevant to an assessment of the existing federal Hours-Of-Service (HOS) regulations, which has been examining the 11-hour driving period for truck safety. The study was in response to public criticism over the safety aspect of a regulatory increase of driving from 10 to 11 hours, since the regulations changed in 2005.

“This had been a contention with some, that allowing drivers to drive an extra hour would significantly increase crashes, but that contention was not supported in our study,” says Richard Hanowski, the director of the Centre for Truck and Bus Safety at Virginia Tech Transportation Institute, who headed up a research project funded by the US Federal Motor Carrier Safety Administration (FMCSA).

The findings of this research project were discussed over a recent online forum, or “Webinar,” with the intention of promoting the findings, and to encourage safety at the wheel, especially within that first hour of driving, according to the chief of the FMCSA research division.

“This was really one of the main purposes of this Webinar: to get the message out to safety managers that the first hour of driving can be the most dangerous and that safety managers need to convey to their drivers, the importance of taking measures, (and) to be fully awake prior to starting their drive,” says Martin Walker, who also offers this advice to truck drivers: “Don’t roll out of the sleeper berth and start driving: Have breakfast. Exercise. Shower. Do something to be fully alert before you start driving in the morning.”

In analyzing the high incidence of first-hour crashes the researchers considered circadian lows versus circadian highs (a 24- hour cycle in the physiological process), but found nothing significant in that analysis.

The study also considered traffic density, with no definite conclusion as to why the first hour of the driver’s work day was the most accident-prone -at 14.7%, with a leveling out and much fewer incidents throughout the day.

“There is a spike in the first hour, and everything else is about the same,” says Hanowski, who offered no rationale, but could only presume that the problem with the first hour of driving might be related to sleep inertia, including the “take-off” and “landing” function of driving.

These are all hypothetical reasons that could be considered by fleet managers, according to the transportation expert, who doubted that any federal regulations would be considered.

“The first hour spike was an interesting finding, but I don’t believe there is anything that FMCSA can do about that, in terms of regulations anyway,” he says. “In my opinion, addressing that would fall with the fleet safety managers, and the drivers, of course.”

Hanowski recommends that fleet managers alert drivers about the importance of being cautious, observant, and practicing defensive driving.

While the research director has his own hypothetical rationale for the spike in crashes, he says the reality is probably quite different from one fleet to another.

“I suspect that much of it might be attributed to the more complex driving environment that many of our study drivers came across in the early stages of their drive: intersections, merging, and most importantly, interacting with other vehicles,” he says, while offering further hypothetical reasoning.

“I think that this might carry over to other hours as well, given these same conditions. That is: it may not be the hour so much as the complex driving environment and heavy traffic that may occur early in their drive. So, the takeaway would be that drivers need to practice safe, defensive driving at all times, but especially when they are in complex, high demand situations.”

The research project also considered the increase in off-duty time from eight to 10 hours, an HoS revision implemented in 2003, which allowed drivers to get more sleep: approximately one hour more than under the former HoS regulations.

It is a revision that has the researchers wondering about a correlation with high first-hour crash incidents.

“An important question associated with this change was: does the additional one hour of allowable driving time, increase crash risk?” asks Hanowski.

The data for this research project was collected with the participation of three trucking companies.

The test trucking companies operated during normal, revenueproducing runs, with 103 drivers driving an average of 46 trucks for about 13 weeks.

The trucks were fitted with a variety of data acquisition systems, including “drowsy driver warning systems,” and four video cameras that were placed in optimal locations on the trucks.

Over 100 data measures on driving performance were collected, which was considered a considerable achievement, according to Hanowski.

“As far as I know, this is the most complete on-road study ever conducted.”