What is the defined hours for the circadian low period based on local time?

The defined hours for the circadian low period, which is a time when human alertness is typically at its lowest, are generally recognized to be from 0130 to 0400 based on local time. This range is critical for understanding fatigue management, particularly for operations involving flight and safety-sensitive tasks.

During this timeframe, individuals are biologically predisposed to experience decreased performance and heightened levels of fatigue, which can significantly impact decision-making and reaction times. Recognizing and addressing this period is essential for ensuring the safety and efficiency of operations, particularly in aviation and other sectors that demand high levels of attention and responsiveness.

Other time ranges listed do not align with established research on circadian rhythms and fatigue management. Understanding the specific defined hours helps to create effective schedules, training programs, and safety procedures that account for human biological patterns.