Effects of carbon monoxide on behavior in monkeys in relation to human fire hazard

Although studies have been made of the behavioral effects of low levels of carbon monoxide in man, there is little information on the behavioral incapacitation resulting from short exposures to high concentrations likely to be encountered in fires. Monkeys, trained to perform behavioral tasks during exposures to 900 ppm carbon monoxide, were seriously affected after 20 to 30 min exposure, achieving carboxyhemoglobin levels of 25-30%. The tests were as sensitive as tests in man for detecting psychomotor deficits induced by carbon monoxide, and measurements of carbon dioxide production presented a more sensitive method for detecting early deficits. It is concluded that a man exposed to 1000 ppm carbon monoxide while engaged in light activity (e.g., walking) could be seriously affected within 30 min.