The required time off between scheduled work shifts became a topic for national debate in April 2011 when air traffic controllers were caught asleep at the wheel. Other jobs also seem to call for an adequate rest period between shifts as a matter of common sense, but this does not mean a single law requires a minimum amount of rest between shifts.

General Labor Laws

No generalized labor laws require a certain amount of time off to be scheduled between work shifts. Surprising as it might sound, no laws prevent employers from scheduling workers for 144 hours out of every week, provided that the employer is in compliance with other wage-and-hour laws, such as overtime. Laws that require a certain amount of hours between shifts are usually targeted to specific industries where worker fatigue can endanger large numbers of people.

Airline Travel

Laws do prescribe a minimum rest period between shifts for both air traffic controllers and airline pilots. The amount of time between shifts for airline pilots was increased by 13 percent in September 2010 -- up to nine hours. This was the first increase in 15 years, according to "The Statesman" newspaper of Austin, Texas. In April 2011, following a spate of incidents where air traffic controllers fell asleep on the job, the Federal Aviation Administration increased the minimum rest period for air traffic controllers to nine hours.

Rail Workers

Rail workers are subject to similar laws allowing for adequate rest between shifts. This includes not only time spent working but "limbo time," or time spent waiting around for freight. If the time worked plus limbo time is more than 12 hours, the rail worker must have 10 hours of uninterrupted rest in addition to rest time equaling the number of limbo time hours that made the shift go over 12 hours. For example, if an employee worked for 15 hours with five hours of limbo time, he would be entitled to 15 hours of rest between shifts.

Truck Drivers

Truck drivers are another industry with a government-mandated rest period. Bus drivers are also subject to the same regulations as commercial truck drivers. These guidelines require eight hours of rest after no more than 10 hours of operating a commercial vehicle. This means that commercial truck and bus drivers may work as many as 16 hours in a single 24-hour period.