Emergency physicians are exposed to a variety of occupational hazards. Among these are infectious diseases, such the human immunodeficiency virus, hepatitis B and C viruses, and tuberculosis. Hepatitis G virus is transmissible but may not be a cause of illness. The likelihood of being exposed to these agents appears to be higher in the ED than other medical settings but estimates of the prevalence of these diseases in the ED vary, depending on the patient population served. Estimates of risk for contracting these infections are reviewed. Measures to prevent these exposures can reduce risk, but compliance is low, particularly for those involving changes in the behavior of emergency physicians (such as not recapping needles). Latex allergy is a hazard of health care workers. Its prevalence is reported to be quite high, but these findings are difficult to interpret in the absence of a universally accepted definition of the condition. Its prevalence in emergency physicians is not known. Other noninfectious hazards include workplace violence and exposure to nitrous oxide. The health effects of rotating shift work may put emergency physicians at increased risk of coronary artery disease and impaired reproductive health. Emotional stress is another hazard of emergency physicians, and may lead to burnout.