For a worker to be entitled to workers compensation they must suffer an injury. And that raises a deceptively subtle question: what exactly is an injury?

The Workers Compensation Act defines two types of injury which may be compensable: personal and disease. It also sets out tests to determine whether an employer is liable for either type.

Personal injury

Some injuries are clearly personal, a broken leg for example.

However (and this is where the subtlety arises), the courts have held that personal injury also includes pathological events such as a burst blood vessel in the brain (leading to a hemorrhage into the brain). The bursting of the blood vessel is a personal injury. The hemorrhage may also cause (personal) injury to the brain.

Next question then: what connection with employment is required in order for a worker who has suffered a personal injury to be entitled to workers compensation payments?

To attract compensation, the following tests apply to the injury:

  1. It must occur "in the course of" the worker's employment. The course of employment is a temporal concept. That is, it covers the period during which you are working.

    However, "the course of employment" can also include activities that are incidental to employment. For instance, let's assume you arrive at work and before turning on your computer you go into the kitchen to make a cup of coffee. If you spill boiling water on yourself, you will have suffered a personal injury "in the course of" your employment. That is because in making a cup of coffee you were engaged in an activity which was reasonably incidental to your job.

    A further example is if an employer arranges a sporting event for staff. If a staff member is injured while participating in that event, even if it is outside normal work hours, they will have suffered injury "in the course of" their employment because their employer arranged the event. The injury may also be compensable if the employer encouraged the worker to attend a sporting event that wasn't arranged by the employer.

  2. If a worker does not suffer personal injury "in the course of" their employment, they may still be entitled to compensation if their injury "arose out of employment". That test will be satisfied if the worker's employment in their job caused, or to a material extent contributed to, the injury.

  3. However, even if a worker suffers a personal injury arising out of or in the course of their employment, to be entitled to compensation they must also establish that their employment was a substantial contributing factor to the injury.

    That requires a real and substantial causal connection between the worker's employment and the injury.

    This requirement has been watered down by the courts and the Personal Injury Commission to the point that it almost appears that if a person is at work when they are injured, employment will be found to be a substantial contributing factor. For instance, if you are sitting at work and your knee gives out when you stand, resulting in pathology, employment is likely to be found to have been a substantial contributing factor in your injury.

Disease injury

The first question is: what is a disease? It is not always easy to differentiate between a personal injury and a disease injury.

The cases tell us a disease is a morbid condition of the body that may be initiated by some external cause or be idiopathic. Examples include Covid infection, repetitive strain injury and, often, psychological conditions.

The test for determining whether a disease is compensable is different from that for a personal injury. The legislation defines two types of disease injury and provides tests for whether or not they are compensable:

  1. A disease which develops in the course of a worker's employment. For it to be compensable, the worker has to establish their employment was the main contributing factor in them developing the disease.

  2. If a worker has a pre-existing disease, the condition can be compensable if the disease is aggravated in the course of their employment, and their employment was the main contributing factor in that aggravation. A common example is pre-existing degenerative back conditions aggravated by work.

    Note that for a disease injury to attract compensation, employment must be the main contributing factor. This is a higher threshold than for personal injuries, where work must merely be a substantial contributing factor.

    What's the difference between the two? Case law tells us there can be more than one substantial contributing factor to an injury, but only one main contributing factor.

    There are many liability issues in workers compensation law, of which this article only covers two. However, to get to first base, a worker must satisfy the liability tests relating to personal injuries or disease injuries. If they do not satisfy the relevant tests, they are most unlikely to succeed in any attempt to receive workers compensation.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.