Most businesses with employees are required to carry worker's compensation insurance in case an employee is hurt while on the job. The first comprehensive state worker's comp law was passed in Wisconsin in 1911 and within a few decades every state had their own version. Worker's compensation is designed to protect both the employee and the employer: the employee is guaranteed medical coverage and often a portion of lost wages while unable to work and the employer doesn't have to worry about lawsuits from injuries. Although each state has their own worker's compensation laws for the most part the coverage is the same. The key to determining whether an injury is covered or not lies in the determination of whether the employee was on company time when the incident occurred.

Covered Injuries

Any injury that occurs on the clock is covered by worker's comp. The most common injury falls under the category of overexertion and usually results in a strained muscle or injured joint. Jobs where physical exertion is required see the majority of overexertion injuries. The second most common is a slip, trip, or fall injury and most often occur due to a wet or slippery floor surface. Other typical worker's comp injury claims are due to falling to a lower level such as on a staircase or ladder, being struck by or against an object, machinery accidents, repetitive motion injuries such as carpal tunnel syndrome, and injuries due to workplace violence.

An injury may be covered even if the worker had a preexisting condition if the condition was aggravated by required work. An example would be an employee with a slipped disc in their lower back that was required to lift during their job and suffered further injury to their spinal condition. Likewise, a worker might have a sore shoulder before slipping on a wet floor and suffering a detached rotator cuff during the accident. In both cases the medical condition would be covered under worker's compensation.

Occupational Diseases

Diseases that result from job exposure are also covered under worker's compensation laws. The key to determination is whether the employee was directly exposed to the cause while at work. For example, lung cancer is rather common and would not normally be considered an occupational disease but if the worker was exposed to asbestos or similar lung cancer carcinogen they would most likely be covered. If an employee develops hearing loss due to noise exposure on the job it can be considered worker's comp and the same goes for asthma and allergies if the employee has been exposed to known substances that cause or aggravate the conditions.

Other worker's comp occupational diseases that would most likely be covered are:

  • A nurse who contracts tuberculosis
  • A firefighter who develops mesothelioma
  • A lab worker who acquires hepatitis
  • A dishwasher who acquires contact dermatitis

Because the worker's compensation determination of occupational disease is broad an ill worker should err on the side of caution if they're not sure whether the cause is work related. Most states have an Occupational Diseases Committee that will make the determination on a case-by-case level.


As with most laws there are additions to the worker's comp injury rules. While an accident or injury that occurs on the way to or from the job is not covered if the employee drives a company vehicle it probably is. Likewise, if an employee is driving as part of their job such as making deliveries it is most likely covered by worker's compensation. If an employee drives for a living they are covered. Traveling for a business event would be covered.

If an employee clocks out and goes off premises for lunch they are not covered, but if they pick up lunch for their employer while they're out they are covered. If they clock out and eat lunch in the company lunchroom and fall while off the clock they're probably covered.

Emotional or mental stress-related injuries are covered but are more difficult to prove as the worker must show it was not caused by events in their personal life and the stress has reached a level of disability in order prove worker's comp coverage.

If a worker is injured at a company picnic or similar event they're not covered, but if attendance at the event was mandatory they most likely will be. Because employees and employers are unique unclear injury claims are determined on a case-by-case basis.


There are quite a few exceptions to worker's comp injury claims. An employee who is injured while intoxicated or under the influence of illegal drugs is not covered, nor is a worker who is injured during a fight if the injury is due to their own misconduct. If an employee is hurt while violating a clear company policy, they won't be covered unless the policy is commonly ignored by the majority.

If an employee purposely injures themselves it won't be covered under worker's comp insurance. An injury that occurs during a crime isn't covered, either. An accident that occurs during "horseplay" won't be covered unless the play is commonly ignored and condoned by management.


Not all workers are covered by worker's compensation insurance. If an employee is on the company payroll, the employer takes deductions from their pay, and the employer lists them as an employee on their worker's comp insurance roll they are definitely covered. Staffing agency or "temp" workers are usually covered either by the staffing agency or the special employer.

Worker's who may not be covered are listed as exceptions in the state in which they are employed. Examples of exempt employees are:

  • Agricultural and farm workers
  • Domestic workers
  • Seasonal or casual workers

Undocumented immigrant workers are covered under worker's comp laws in most states, but this area of law is evolving.

Remember, while insurance can be expensive your worker's comp insurance protects you from lawsuits due to injuries on the job and an uninsured workersker retains the right to sue.