The Department of Labor's Wages and Hours Division enforces national laws regarding workers' rights. The main set of laws regarding labor is the Federal Labor Standards Act. The FLSA contains regulations about minimum wage, overtime, child labor and family leave. One section is also devoted explicitly to hours worked and rest periods.
There are no specific laws regarding a mandatory break or rest period for employees over age 16. The Wage and Hour Division, however, refers to the effectiveness of short breaks as well as meal breaks in the materials available to employers. It suggests that short breaks of less than 20 minutes are common and "promote the efficiency of the employee." When breaks are offered, the law states that short breaks (five to 20 minutes) are considered "worked hours" and must be paid.
State vs. Federal Regulations
Nine states--California, Colorado, Illinois , Kentucky, Minnesota, Nevada, Oregon, Vermont and Washington--have specific laws regarding rest periods and meal breaks. In states with labor standards additional to those outlined in the Fair Labor Standards Act, the employee is always entitled to the higher standard. Therefore, in the case of breaks, employers would be required to offer rest periods as outlined by state laws.
Workplaces protected by a collective bargaining agreement or union contract have different policies. Occasionally, these contracts outline specific policies regarding breaks. The federal law protects the rights of employees to be covered under these contracts, therefore protecting their rights to the mandatory breaks listed in them.