Factors contributing to standard threshold shifts (STSs) other than workplace noise exposure were examined. The study material consisted of sequential audiograms of 1693 employees at six sites of a large publishing company who were in a hearing conservation program. The data were analyzed to assess the effects of occupational noise exposure, nonoccupational noise exposures, self reported medical conditions, sex, and age on the STS according to OSHA criteria. OSHA considered an STS to be an average change in hearing threshold of 10 decibels or more occurring in either ear at 2000, 3000, or 4000 hertz relative to the baseline audiogram. Noise exposures at the worksites ranged from 88 to 92 decibels-A (dBA), average 90dBA. Increases in STS were not significantly related to occupational noise exposure. Males were more likely to develop increases in STS than females. Females who showed increases in STS were older than males who developed STSs. Hypertension, histories of head injury, high fever, and measles, and participating in hunting and shooting were significantly associated with increases in STS. Employees who had impaired hearing when they entered a hearing conservation program were more likely to show increases in STS than those with normal hearing. The authors conclude that factors outside the work environment can contribute to increases in STS. When evaluating the effect of noisy workplace environments, companies should assess each employee individually according to his medical history and nonoccupational noise exposures.