ABSTRACT
Although human performance varies greatly between and within individuals, it can generally be predicted from a number of physiological and psychophysiological factors that are common to all humankind, regardless of the operational environment. These include the effects that circadian influences, disrupted sleep, sleep loss, physical exertion, and other factors, including caffeine, alcohol, and over-the-counter medications, have on performance, cognition, and response time, and therefore on the safety of any planned or emergency response operation. Particularly when operational demands require sustained performance in a hazardous time- and cost-sensitive environment, such as during spill response operations, these physiological considerations must be factored into the planning and execution of response operations if maximal safety, effectiveness, and cost efficiency are to be preserved.