Research Project

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Flexible Sleeper Berth Pilot Program


To conduct a pilot study to demonstrate how split-sleep could be used to improve driver rest and alertness.


Scientific literature suggests that statutory or regulatory limitations on work hours may not be sufficient to prevent worker fatigue. FMCSA conducted an in-residence laboratory study from January 2010 to May 2011 where three sleep conditions were examined. Results indicate that daytime consolidated sleep leads to less total sleep time, increased driver sleepiness, and increased blood glucose and testosterone levels by work week’s end. Results for split-sleep conditions indicate that when consolidated nighttime sleep is not possible, split-sleep is preferable to consolidated daytime sleep. Additionally, during listening sessions for the hours-of-service (HOS) rulemaking, many drivers indicated that they would like some regulatory flexibility to be able to sleep when they become tired or when traffic is congested (i.e., exemption from the requirement for consolidated sleeper berth time). This combination of research and industry feedback informs the current sleeper berth and split-sleep pilot study.


The Flexible Sleeper Berth Pilot Program is a field operational test allowing regulatory flexibility in the HOS provisions. Carriers that would like flexibility with the sleeper berth provision will be identified. There will be constraints on the use of split-sleep for team driving. Driver alertness and changes in health metrics will be measured. The sample size goal is 200 drivers—stratified by size of carrier—to include drivers from large, medium, and small carriers who regularly use their sleeper berth. The proposed research design is an “in-subject and between-subject design,” where alertness both within subjects and across subjects will be compared for drivers who operate under different alternatives within the HOS provisions. Drivers will be remunerated for the time spent performing tasks required for the study. The study team will collect data on a minimum of 50 drivers per 90-day participation cycle. To achieve the goal of 200 participants, the study team will collect data on five 90-day cycles. An extra cycle may be needed for driver attrition. Data collection can come from a multitude of sources, including analysis of variance-based strategies that are applied to analyze mixed effects within and between subjects.


Addressing carriers that have expressed a desire for flexibility in sleeper berth provisions; field data on the efficacy of allowing split-sleep in conjunction with a fatigue management program; and measures of driver alertness, sleep quantity, and changes in health metrics.



November 2015: Project kick-off
December 2015: Finalize project work plan; literature review
March 2016: Develop OMB ICR
September 2016: Develop pilot program Web site and study protocol instructional materials
June 2017: ICR 60-day notice posted.
Oct 2017: ICR 30-day notice posted.
November 2017: ICR sent to OMB for approval.
February 2018: Five-driver pre-test is conducted
Fall 2018: Pilot study begins
Summer 2019:  Data collection ends


FY15 Funding: $2,500,000
FY17 Funding: $195,100

Project Manager:

For more information, contact Nicole Michel of the Research Division at (202) 366-4354 or


Virginia Tech Transportation Institute
Updated: Wednesday, August 22, 2018
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