Fatigue is the body’s normal reaction to a physical or mental stress of prolonged duration. The onset of fatigue is insidious, and the symptoms may not be recognized until the person has reached a high degree of fatigue. It is one of the main contributors to maintenance errors and must be addressed if we are to improve safety and reduce maintenance errors. This lesson will provide a basic understanding of fatigue, what can be done to reduce fatigue and its impact on performance.