The sleep math
NIOSH guidance for extended work hours is specific: protect at least 10 consecutive hours off duty each day so a worker can get 7 to 8 hours of sleep, because shorter off-duty periods compound the fatigue of long shifts. Night work and extended hours are the classic culprits, since they shorten and disrupt sleep. Fatigue degrades reaction time, judgment, and hazard perception, which is why it shows up in the industry's leading fatal event rather than in the safety meeting.
The schedule is the control
Oilfield crews work 12-hour tours, 14-day rotations, and long commutes to remote locations, and all of that counts as time that is not rest. Rotation design, night shift limits, and enforced rest periods are management controls, and the trucking side already carries the same logic in the hours-of-service rules. A schedule built without a fatigue review is a safety decision made by default.
The record catches the pattern
Hours worked, duty logs, and incident timing tell the story: a cluster of near-misses, vehicle incidents, or paperwork errors on long shifts is a signal, not bad luck. NIOSH's FOG database shows vehicle incidents at about 27 percent of oil and gas extraction worker fatalities from 2014 to 2019, so the commute and the route carry the industry's biggest risk. Fatigue rounds and fit-for-duty checks belong in the same system as the incident data, because both are about the human in the loop.
Fatigue management overlaps the other records a crew generates: near-miss reports, hours-of-service logs, and overtime records. If duty hours and incidents are tracked in separate notebooks, an operations audit will show which crews are being scheduled past the point the data says is safe.