Hospital emergency codes are coded messages often announced over a public address system of a hospital to alert staff to various classes of on-site emergencies. The use of codes is intended to convey essential information quickly and with minimal misunderstanding to staff while preventing stress and panic among visitors to the hospital. Such codes are sometimes posted on placards throughout the hospital or are printed on employee identification badges for ready reference.
Hospital emergency codes have often varied widely by location, even between hospitals in the same community. Confusion over these codes has led to the proposal for and sometimes adoption of standardized codes. In many American, Canadian, New Zealand and Australian hospitals, for example "code blue" indicates a patient has entered cardiac arrest, while "code red" indicates that a fire has broken out somewhere in the hospital facility.