FMCSA to Conduct Test on Split-Sleeper Fatigue

This story appears in the Nov. 3 print edition of Transport Topics.

ALEXANDRIA, Va. — The Federal Motor Carrier Safety Administration plans to conduct a 90-day on-highway pilot program to evaluate whether split sleeper-berth breaks contribute to truck-driver fatigue, a top agency official said last week.

Martin Walker, chief of FMCSA’s research division, told the agency’s Motor Carrier Safety Advisory Committee that the pilot contract could be awarded by mid-December but that the actual data collection would likely not begin until early 2016.

It could take a year for the pilot proposal to wind through the agency’s administrative process, gain White House approval, and for officials to recruit as many as 200 truck drivers to participate, Walker said.

The drivers ideally would be a mix of independent operators and come from small, medium and large motor carriers, Walker said.

The so-called flexible sleeper berth pilot project would allow drivers to split their eight hours of sleep into at least two periods, Walker said. That, for example, would allow drivers to take two-hour daytime naps that would not count against their 14-hour allowable daily work time.

Before the pilot can begin, agency researchers will need to assemble a peer review group on methodology, and then determine whether drivers can split their sleep any way they want or whether it will be in required two-to-four hour blocks or two four-hour periods, Walker said.

Prior to 2005, federal regulations had for decades permitted drivers to split their rest in sleeper berths. However, since then solo and team drivers have not been allowed to split rest except in very rare instances.

“The concern has been that when drivers get tired they want the ability to pull over and not have it count against the 14-hour clock,” Walker said.

Previous laboratory research has tested the premise that greater flexibility in truck driver sleep time may result in improved safety outcomes by improving or sustaining driver alertness.

One of those lab tests, a 2010-2011 FMCSA split sleep study with 53 participants, convinced the agency to test the idea under real-world conditions.

The objective of the 2010-2011 lab study was to evaluate the consequences for safety and health of split sleep versus consolidated sleep periods by comparing the effects of consolidated nighttime sleep, split sleep and consolidated daytime sleep on total sleep time, performance and biomedical measures correlated with health outcomes over the long term.

The study found that the daytime consolidated sleep group slept less, had increased sleepiness, and an increase in blood glucose and testosterone at the end of the workweek. 

However, the lab study results suggested that when consolidated nighttime sleep was not possible, split sleep was preferable to consolidated daytime sleep.

Now the agency plans to move the study out of the lab and onto highways to reality test what the lab study suggested, Walker said.

Because it will be important that drivers log accurate time driving, sleeping and otherwise working for accurate data, the pilot will require that electronic logging devices be placed in all the trucks participating in the pilot, Walker said.

The pilot also will use an array of technologies to measure such possible signs of driver fatigue as eye closures, lane departures and hard braking for drivers splitting their sleep schedules.

Data to be collected will include driver behavior, reaction time, vital signs, roadside violations and crashes.