The principal objective of this study was to investigate whether or not nurses' compliance with universal precautions procedures improved after the mandatory Occupational Safety and Health Administration regulations were implemented in 1992. Two random samples of registered nurses and licensed practical nurses registered in Tennessee responded to survey questionnaires measuring universal precautions compliance and practice barriers to compliance in 1991 and 1993 (n = 306). The 1993 sample of nurses reported significantly greater compliance with universal precautions (p < 0.001) than the 1991 sample. The most noteworthy improvement between the 1991 and the 1993 groups was a significant increase in compliance for patients described as HIV/HBV-status unknown and HIV/HBV-negative (p < 0.001). Practice barriers hindering compliance with universal precautions decreased significantly (p < 0.001) in the 1991-1993 time frame. Problematic practice barriers identified in both groups were needle recapping, preference for isolation door signs, and concerns about offending patients and visitors.