To test whether prevalence of hypertension was higher among these bus drivers than among employed individuals in general, drivers were compared to three groups: individuals from both a national and local health survey and individuals undergoing baseline health exams prior to employment as bus drivers. 2. After adjustment for age and race, hypertension rates for bus drivers were significantly greater than rates for the three comparison groups. 3. These findings support previous results from international studies of bus drivers suggesting that exposure to the occupation of driving a bus may carry increased health risk.