PROJECT-AQUARIUS .9. RELATIVE INFLUENCE OF JOB DEMANDS AND PERSONAL FACTORS ON THE ENERGY-EXPENDITURE, STRAIN, AND PRODUCTIVITY OF MEN SUPPRESSING WILDLAND FIRES

Studies of hand-tool crews suppressing summer bushfires showed wide va riations in firefighters' energy expenditure (EE) and productivity, an d in their physiological and subjective responses ('strains'). Analyse s of variance showed that (1) EE while using a rakehoe ('raking') vari ed mainly between subjects (i.e. with personal factors); (2) sweat rat e, thigh skin temperature, and the proportion of the work time spent i n each activity of fire suppression varied mainly between days of fire line construction (i.e. with job demands); and (3) heart rate, rectal temperature, perceived exertion, productivity, efficiency, and all-act ivities EE varied more or less equally between subjects and days, each of which explained about one third of the variation. These findings s how that personal factors were no less influential than were the deman ds of the job.