BACKGROUND Emergency department health care workers frequently provide care to patients who are in unstable condition, bleeding, or in a crisis situation. To identify the variables described in the Health Belief Model affecting health care workers' compliance with practices and devices believed to reduce exposure to patients' blood, the staff of a level II trauma center were surveyed for knowledge, compliance, and training regarding universal precautions. METHODS Fifty-three health care workers responded to an anonymous, self-report, 50-item questionnaire. Significant differences in mean scores were determined by use of a two-tailed t test. RESULTS Health care workers estimated they were most likely to perform handwashing after contact with body fluids and to wear gloves if contact with blood was anticipated. The most common obstacles to compliance with universal precautions were lack of time, patients perceived to be at lower risk for HIV or hepatitis B infections, and interference with technical skills. Health care workers with more than three perceived obstacles to universal precautions were less likely to use gloves (p < 0.05) if contact with blood was anticipated. Health care workers with a higher number of training experiences in universal precautions were more likely to use gloves if contact with blood was anticipated (p < 0.05) and less likely to recap a needle after giving an intravascular injection (p < 0.05), drawing a blood gas sample (p < 0.05), or injecting medication into an intravenous line (p < 0.05). CONCLUSIONS The application of the Health Belief Model to this problem suggests that an integrated approach is appropriate. Such an approach should incorporate engineering controls, cognitive approaches, behavior modification strategies, and training experiences to improve skills and dexterity.