James F. Mahoney, Attorney

The Impact of Driving, Non-Driving Work
and Rest Breaks on Driving Performance

The assessment of the drivers’ workday determined that drivers spent
66% of their shift driving, 23% in non-driving work, and 11% resting

 Subscribe  •  Return to Trucking News Index

An FMCSA report issued this month reflects on data collected in the Naturalistic Truck Driving Study and included 97 drivers and about 735,000 miles of continuous driving data and focused on workday duties and the effects on fatigue and correlation with accidents.

The assessment of the drivers’ workday determined that:

  • drivers spent 66 percent of their shift driving,

  • 23 percent in non-driving work, and

  • 11 percent resting.

Analyses suggested that the risk of being involved in a Safety Critical Event increased as work hours increased. That is, if a driver begins the day with several hours of non-driving work, followed by driving that goes deep into the 14-hour workday, risk of a safety event was found to increase. Breaks from driving were found to be beneficial in reducing these safety critical events, even breaks taken late in driving time, but the effects of taking breaks during drive time seemed to be limited to avoiding these SCE’s for only an hour post-break.

The findings confirm what most people have understood from the dawn of the Industrial Age, that is, “Worker (Driver), pace yourself” and plan your day (trip) with restful breaks.

Although the report didn't intend to highlight trucking inefficiencies, it's revealing to see the economic loss to the industry knowing that "drivers" spend a quarter of their workday in non-driving activities.

Another report released by the FMCSA this month seems to suggest an opposite conclusion on fatigue. It was drawn from a study of split-shift bus operators (start early – long interim break – finish driving late). The study revealed that operators working split schedules are more susceptible to fatigue than those working straight schedules. The drivers working split schedules indicated less sleep, long driving hours and long workdays. According to the study, these are characteristics of a fatigue-inducing work schedule.

Seems conclusory. Fodder for the sleep apnea vendor lobby.

How the Agency can regulate circadian rhythms across a broad spectrum of CMV drivers, routes and strategies is, to say the least, a difficult task. The new HOS regs effective date has been pushed back for additional comment time. These conflicting studies will help sooo much.

An ATRI study this month found contradictory evidence and refuted their own 2005 study that so strongly linked certain driver behaviors to risk of crash involvement. The latest study correlates a number of moving violations – failure to signal, speeding - or previous accident involvement as predictive of future crashes.

All these studies are certainly well-intentioned and maybe even peer-reviewed, but we should use them not as absolute truth, but simply as markers on the way to studying our specific operations and the root cause of our losses for consideration of change of behavior.