Stephen M Popkin

U.S. Department of Transportation · Volpe National Transportation Systems Center

Fatigue is regarded as a major contributor to workplace and highway morbidity and mortality. While the scientific literature is replete with studies that can be traced back more than a hundred years, much remains to be done to improve our knowledge of and ability to alleviate the consequences of fatigue. Moreover, given the dramatic transformation...

Although there has been a significant amount of research on fatigue globally, it remains a major contributor to workplace and highway mortality and morbidity. Given its importance, a Hopkinton Conference was organized to review and discuss the state of knowledge in the area and to define future directions for research aimed at preventing or mitigat...

The US workforce is aging. At the same time, there are a record number of open positions in the transportation sector, which has traditionally been a well-paying, but stressful and schedule-dependent, occupation. Due to increasing longevity, need, and ability to work, a possible solution to the transportation workforce shortfall may lie within the...

Few studies have examined napping in irregular work schedules such as those experienced by freight locomotive engineers. The current study examined the effect of napping in irregular work schedules on sleep length and three subjective measures: ability to go to sleep, ability to stay asleep, and a feeling of being well-rested upon awakening. One hu...

Sustained human performance is critical to job and mission success in many federal agencies including national defense, aerospace exploration, and transportation. For the responsible agencies, applications of the basic biomedical and applied human factors science provide the best available solutions to help individuals perform more effectively and...

The human circadian system is sensitive to environmental conditions, such as those created by shift work, that affect the timing and duration of sleep. Previous research on the effects of shift work, however, has focused primarily on regularly scheduled shifts. Few studies have focused on irregular and unpredictable on-call shift systems, such as t...

Locomotive engineers (train drivers) on irregular work schedules reported a general coffee consumption rate higher than that reported by a comparison sample of permanent shift factory workers. The present study examines the impact of this consumption on workday and non-workday sleep behaviour and mood ratings. Twenty-seven engineers and their spous...