1.   The researchers sought to determine if rest periods would reduce worker fatigue and therefore contribute to increased output across the day.

2.   Worker fatigue is a major contributor to accidents.

3.   But dealing with worker fatigue in the railroad industry has proved mettlesome for the federal government.

4.   The FRA cited chronic worker fatigue and other problems in its sweeping safety review of Union Pacific.

5.   Union Pacific has since instituted an employee time-off program aimed at cutting worker fatigue.

6.   Worker fatigue, heavy workloads for train dispatchers, neglected mechanical inspections and worker intimidation all contributed to unsafe practices, the report said.

7.   A state official blamed the shutdown Sunday night on worker fatigue.

8.   It means worker fatigue and fear of additional layoffs.