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British Nuclear Warning System
This page gives an overview of the development of the UK's early warning system while avoiding too much technical details. Should you wish to read an in depth description of the two incarnations of the warning system, please use the website menu and select the WB400 & WB600 for the system between the sixties and eighties, or WB1400 Parts 1 & 2 for the eighties to its closure in 1992.
The 'ATTACK MESSAGE WHITE' is 60 seconds sounding of the siren with a steady note indicated you could leave your shelter as the raid had been thwarted or if there had been nuclear explosions, the fallout radiation had dropped to a safe level. The information about the unexpected strike would have been fed back via the UKWMO communications network to its Preston Sector Headquarters and the Air Defence Operations Centre at RAF High Wycombe, so either could issue the Attack Warning for the rest of the country. As a backup, in case both National Centres be disabled, or the HANDEL network itself, the 25 UKWMO Groups HQs were also instructed to call each CCP within their area requesting they broadcast the Attack Warning Red.
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