Abstract
Thirty adult, nonsmokers were exposed for four hours to one of three concentrations of carbon monoxide (CO) 5 ppm, 35 ppm, and 70 ppm to produce blood levels of either 1%, 3%, or 5% carboxyhemoglobin (COHb) after the third hour of exposure. Performance in the double blind study was assessed by a tracking task paired with a peripheral monitoring task, each possessing two levels of difficulty. The results indicated that visual-manual tracking was significantly impaired by about 30%, during the fourth hour of exposure to 70 ppm of CO, when 5% COHb was reached, as compared to performance at 5 ppm and 35 ppm. The impairment occurred only during the high frequency tracking condition. Response times of subjects to the peripheral light-intensity-changes also increased during the third and fourth hours. The findings suggested that an assessment of the effects of low-level CO on human performance should include an analysis of the demand characteristics of the tasks as well as data on concentration and exposure duration.

This publication has 19 references indexed in Scilit: