The IEA (International Ergonomics Association) Council adopted the following official definition of ergonomics in August 2000: "Ergonomics (or human factors) is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance. Ergonomists contribute to the design and evaluation of tasks, jobs, products, environments and systems in order to make them compatible with the needs, abilities and limitations of people."

Simpler definitions of ergonomics include:

Fitting the job to the worker.
Designing for human use.

Problem jobs often involve one or more of the following primary risk factors:
1. Poor postures
2. High forces
3. Repetition/Duration
4. Environmental (Temperature/Lighting/Noise)

Risk factors should be minimized by implementing effective controls (listed in order of preference):

1.Engineering Controls: This is the preferred control method. The hazard is minimized or eliminated by changing the design of the workplace (or product) or by changing the work sequence procedures. Ergonomic professionals recommend designs and provide alternatives that agree with the capabilities and limitations of people.

2.Administrative Controls: The hazard is minimized by implementing work practices and policies (including job rotation, rest breaks, shift length, overtime, job enlargement, work pace, etc).

3.Personal Protective Equipment (PPE): Equipment worn by the employee to reduce exposure (knee pads, vibration gloves).

It is important to test and evaluate the implemented controls to verify that the control reduced or eliminated the risk and that additional risks were not introduced.

The risk of injury, productivity loss, and poor quality increases as worker capabilities are exceeded. Task requirements should not exceed the capabilities of workers.

Improvement is a continuous process that requires changing the design of workplaces and products. It is important to be proactive, instead of reactive, by solving ergonomic design issues before injuries, quality problems, and productivity losses occur.