CONELRAD (Control of Electromagnetic Radiation) was a method of emergency broadcasting to the public of the United States in the event of enemy attack during the Cold War. It was intended to allow continuous broadcast of civil defense information to the public using radio stations, while rapidly switching the transmitter stations to make the broadcasts unsuitable for Soviet bombers that might attempt to home in on the signals (as was done during World War II, when German radio stations, based in or near cities, were used as beacons by bomber pilots).
U.S. President Harry S. Truman established CONELRAD in 1951. After the development of intercontinental ballistic missiles reduced the likelihood of a bomber attack, CONELRAD was replaced by the Emergency Broadcast System (EBS) on August 5, 1963, which was later replaced by the Emergency Alert System (EAS) on January 1, 1997; all have been administered by the Federal Communications Commission (FCC).
Unlike the EBS and EAS, CONELRAD was never intended for use in local civil emergencies such as severe weather. However, the system's alerting protocol could be used for alerting of a natural disaster by 1957.
Before 1951, there was no systematic way for the U.S. government to communicate with citizens during an emergency. However, broadcasters would typically interrupt normal programming to issue emergency bulletins, as happened during the attack on Pearl Harbor on December 7, 1941 and the first successful tornado warning in 1948. Such bulletins were the forerunner to CONELRAD.
The CONELRAD concept was originally known as the Key Station System. According to an FCC document created during the "Informal Government–Industry Technical Conference" on March 26, 1951:
The primary plan for alerting broadcast stations that are currently being considered by the FCC Study Group is known as the Key Station System. The arrangement requires certain telephone circuits (private wire or direct line to Toll Board) between the Air Defense Control Centers (A.D.C.C.
Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.
L’alerte de quatre minutes était un système d’alerte public conçu par le gouvernement britannique pendant la guerre froide et appliqué de 1953 à 1992. Ce nom tire son origine de la durée approximative à partir du moment où une attaque de missiles nucléaires soviétique contre le Royaume-Uni pouvait être confirmée et l'impact de ces missiles sur leurs cibles. La population devait être avertie au moyen de sirènes anti-aériennes, de la télévision et de la radio, afin d'être incitée à se mettre immédiatement à l'abri.
Un abri antisouffle est un abri destiné à protéger ses occupants des explosions et de l'effet de souffle consécutifs à ces explosions. Les explosions peuvent provenir aussi bien de celles de bombes, ou de chantiers dangereux, comme les raffineries de pétrole et de gaz ou les installations pétrochimiques. Il diffère d'un abri antiatomique, en ce sens que son objectif principal est de protéger des ondes de choc et de la plutôt que des retombées radioactives, comme le fait un abri antiatomique.
A civil defense siren, also known as an air-raid siren or tornado siren, is a siren used to provide an emergency population warning to the general population of approaching danger. It is sometimes sounded again to indicate the danger has passed. Some sirens, especially within small municipalities, are also used to alert the fire department when needed. Initially designed to warn city dwellers of air raids during World War II, they were later used to warn of nuclear attack and natural disasters, such as tornadoes.