How many hours can you work in a day according to OSHA?

The Occupational Safety and Health Administration (OSHA) says that a normal work shift is no more than 8 consecutive hours in a day, with each shift split by at least 8 hours of rest. A normal workweek is 5 such work days.¹ However, this is not binding. OSHA does not penalize employers who demand more.

Do long working hours impact worker safety?

Yes, studies have shown that long or unusual working shifts have a negative impact on worker safety.

One study found that visits to the emergency room from workplace injuries increased nearly threefold outside of regular working hours. Between 6am and 4pm, it was fairly constant at 2 per 200,000. However, outside of this normal shift, the rate jumped to over 5 per 200,000 between the hours of 8pm and 3am, peaking at nearly 7 between midnight and 2am. The increase applied to manual, non-manual, and mixed jobs. The study states that this sharp increase was likely due to worker fatigue and less supervision during off hours.²

Another study found that, when compared to 8-hour shifts:

• 10-hour shifts saw a 13 percent increase in the risks of an accident or error, and
• 12-hour shifts saw a 28 percent increase.³

OSHA recommendations

Because of these increased risks of workplace injury, OSHA recommends that employers generally use a normal work shift. A normal shift:

• consists of no more than 8 consecutive hours,
• happens only 5 days a week, and
• is split from other shifts by at least 8 hours of rest.⁴

OSHA suggests that shifts that call for longer hours, or unusual shifts that call for greater worker flexibility, be used as little as possible.⁵ OSHA says that, if long work schedules are used a lot, it can lead to:

• worker burnout,
• excessive absences,
• use of sick leave,
• fatigue disability, and
• an increase in workplace accidents and injuries.

However, these are only recommendations. They are not binding OSHA rules or regulations.

Are there federal laws that cap the number of hours I can work in a day?

Generally, no, there are no federal laws that limit how many hours you can work in a single day. (Though some state labor laws have maximum hour laws for minors.)

The federal law that applies to all employees is the Fair Labor Standards Act, or FLSA. This law does not regulate how many hours you can work in a day. It also does not regulate how many days you can work in a row.

Minimum wage and overtime

However, the FLSA does mandate the federal minimum wage and employee overtime pay for non-exempt workers. If you are non-exempt, you are entitled to one-and-one-half (1.5) times your regular rate of pay for every hour you work in excess of 40 hours in a workweek.⁶ The Wage and Hour Division at the U.S. Department of Labor (DOL) enforces these provisions of the law.

State laws may provide more generous overtime pay. In California, for example, non-exempt employees are entitled to overtime pay if they work more than:

• 8 hours in a day,
• 40 hours in a week, or
• 6 consecutive days in a row.⁷

By requiring extra pay for overtime hours, state and federal overtime laws may deter employers from making an employee work extremely long hours in a day. However, full-time exempt workers such as professional employees and some salaried employees do not benefit from this deterrence.

Trucking regulations

Some industries, like trucking, do regulate how many hours you can work in a day. The Department of Transportation (DOT) hours of service rules put a daily driving limit on interstate truckers:

• shifts or work periods must be 14 consecutive hours or fewer,
• driving can only be done during 11 hours of that 14-hour period, and
• there must be at least 10 consecutive hours off duty before starting a new shift.⁸

These regulations penalize truckers and their employers for driving longer than the allowed hours.

Does federal law mandate rest or meal periods?

No, federal employment law does not require employers to provide rest or meal periods to employees. However, many state laws do mandate these rest periods.

For example, in California, non-exempt workers are entitled to:

• an unpaid 30-minute meal break if they work more than 5 hours in a day, and
• a paid 10-minute rest break for every 4 hours of work, or substantial fraction thereof.⁹

Additionally, many employers provide them even when they are not required to do so.

Can OSHA cite an employer for causing worker fatigue?

OSHA can cite employers for ignoring the risks of employer fatigue in the workplace. However, it cannot cite employers simply because their workers are tired.

There is no specific OSHA standard or rule concerning extended work shifts. Instead, citations regarding employee fatigue are based on the General Duty Clause of the Occupational Safety and Health Act. This Clause requires employers to furnish a workplace that is free from recognized hazards that are likely to cause injury or death.¹⁰

This means that employers can get cited if they know that their workers are overworked and fatigued, recognize the risks, but do nothing to fix it.¹¹

Additional reading

For more in-depth information, refer to these scholarly articles:

• The Effect of Working Hours on Health – Economics & Human Biology.
• Long Working Hours and Well-being: What We Know, What We Do Not Know, and What We Need to Know – Journal of Business and Psychology.
• The Productivity of Working Hours – The Economic Journal.
• Ethical Issues Relating to the Health Effects of Long Working Hours – Journal of Business Ethics.
• Long working hours, occupational health and the changing nature of work organization – American Journal of Industrial Medicine.

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