In July 1987 and January 1988, forty-six percent (441/955) of randomly selected US hospitals responded to a questionnaire intended to identify their waste disposal practices. Survey responses were received from hospitals in 48 states. United States hospitals generated a median of 6.93 kg of hospital waste per patient per day and infectious waste made up 15% of the total hospital waste. Most hospitals (>90%) considered blood, microbiology, "sharps," communicable disease isolation, pathology, autopsy, and contaminated animal carcass waste as infectious. Other sources of hospital waste that were commonly (>80%) designated infectious were surgical, dialysis, and miscellaneous laboratory waste. The infectious waste was normally (80%) treated via incineration or steam sterilization before disposal, whereas noninfectious waste was discarded directly in a sanitary landfill. Eighty-two percent of these US hospitals are discarding blood, microbiology, sharps, pathology, and contaminated animal carcass waste in accordance with the Centers for Disease Control's recommendations, while the compliance rate for the Environmental Protection Agency's recommendations (excluding optional waste) is 75%. No hospital could identify an infection problem (excluding needle-stick injuries) that was attributable to the disposal of infectious waste. While the management of infectious waste by US hospitals is generally consistent with the Centers for Disease Control's guidelines, many hospitals employ overly inclusive definitions of infectious waste.