The Hours of Service laws (HSL), first enacted in 1907 and most recently amended in 2008, control how many hours train employees, dispatching service employees, and signal employees may work. The statute provides maximum on-duty periods for each group of employees, minimum off-duty periods for train employees and signal employees, and establishes how time on duty is to be calculated. The statute also provides additional limitations on consecutive-days and certain monthly limitations on the activity of train employees.
Because the HSL are currently statutory provisions, not regulations, only Congress can amend them. However, in the Rail Safety Improvement Act of 2008, FRA received regulatory authority to establish hours of service limitations for train employees providing commuter and intercity rail passenger transportation service (passenger train employees). On August 12, 2011, FRA published its final rule providing new limitations for passenger train employees, based on the limitations in the HSL as it existed prior to 2008. The regulation adds a requirement to analyze employee work schedules with fatigue modeling tools, and consecutive-days limitations that recognize the difference between work during daylight hours and work during nighttime hours.