Circadian Variation in Alertness and Performance [Nuclear Regulatory Commission] Law and Legal Definition

According to 10 CFR 26.5 [Title 10 – Energy; Chapter I -- Nuclear Regulatory Commission; Part 26 -- Fitness for Duty Programs; Subpart A -- Administrative Provisions], circadian variation in alertness and performance means “the increases and decreases in alertness and cognitive/motor functioning caused by human physiological processes (e.g., body temperature, release of hormones) that vary on an approximately 24-hour cycle.”