Generally, there are no legal limits except for some employees in the transportation industry (for example, employees involved in the movement of trains and truck drivers), juveniles and employees exposed to hazardous materials. Labor laws limit the number of hours you can work children each week. OSHA also has exposure limits for persons working in hazardous environments (exposed to hazardous materials). Otherwise, the only limits to the number of hours you can work an employee are what you and the employee agree to when the “contract of hire” is set, or later when mutually modified. Of course, you may owe overtime pay. Check if your state law has any limitations.