Hospital employees are at various degrees of risk for development of hepatitis B infections. A retrospective review of surveillance records in five clinical areas at high risk for hepatitis B exposure was carried out to determine its prevalence and incidence in each area. The area surveyed with the highest risk was the emergency department. It was followed, in descending order, by the operating room, the medical and surgical intensive care units, and the dentistry—oral surgery clinic. The surveyed area at the lowest risk was the hemodialysis unit. Strict infection-control guidelines probably minimize the employees' risk to hepatitis in the hemodialysis unit. In the emergency department, however, employees may be increasingly exposed to hepatitis B by dealing with life-threatening problems in an uncontrolled setting.