The American Transportation Research Institute (ATRI) released the findings of its independent evaluation of the Federal Motor Carrier Safety Administration’s (FMCSA) field study report on the new Hours-of-Service (HOS) rules. FMCSA was directed by Congress as part of MAP-21 to study the efficacy of the restart provisions which went into effect July 1, 2013.
FMCSA’s field study collected fatigue measurements from 106 truck drivers during two duty cycles that included two restart breaks. FMCSA stated that their field study results supported the efficacy of the new restart rule. Following a detailed evaluation of the field study report, ATRI identified a variety of technical issues related to research design flaws, validity of measurement techniques and interpretations and data conflicts within and across the study.
ATRI’s Technical Memorandum documents the following issues with FMCSA’s report:
- The field study report purports to have measured differences between restarts with one and two nighttime periods (1 a.m. to 5 .a.m.) but instead measured differences in restarts that range from 34 hours to an unknown/non-limited number of hours off-duty.
- MAP-21 required that the field study be “representative of the drivers and motor carriers regulated by the hours of service regulations” but the study includes, on average, less than 12 days’ worth of data for each of only 106 drivers.
- The FMCSA field study does not present research to support the limitation of the use of the 34-hour restart to once per week (168 hours).
- Use of the 3-minute Psychomotor Vigilance Test (PVT) showed lapses of attention by drivers in both duty cycle groups, but offered no link between the average number of lapses, fatigue and the safe operation of commercial vehicles.
- The two duty cycle groups had lane deviation measurements that differed by 1/10th of a centimeter and the study authors provide no evidence that these findings are relevant or have a nexus to driver fatigue in either of the two groups.
- The difference in sleep obtained by the two duty cycle groups on their restart breaks differed by only six minutes per 24-hour period.
- Average driver scores on the subjective sleepiness scale did not indicate any level of sleepiness.
- The study confirms that drivers in the “two or more nighttime” group are more likely to drive during the day; a time when FMCSA’s own data shows a higher crash risk.
“FMCSA has heard loud and clear from carriers and drivers that the new rules are not advancing safety and are creating additional stress and fatigue on the part of truck drivers,” commented Steve Rush, President of Carbon Express, Inc. in Wharton, NJ. “ATRI’s analysis raises enough questions about FMCSA’s own study that should compel a comprehensive review of the entire rule.”
A copy of this report is available from ATRI at www.atri-online.org.
