The French have long been used to hearing warning sirens at 12noon on the first Wednesday of every month - but, for a brief period, according to the Ministry of Interior, there will be a change in schedule.
New operating software has been installed in the système d’alerte et d’information des populations (SAIP). Rather than overload the system with a full simultaneous nationwide test of all 2,000 sirens, the Ministry of Interior has decided to divide the country into three bands - northern, central, and southern.
During the test period for the new software, warning sirens will sound at 11.45am in the northern band; at 12noon in the central band; and at 12.15pm in the south.
How long the bands will remain in place before the national tests resume has not been specified.
"The establishment of the system of alert and information of populations (SAIP) responds to the need for the mayor, the prefect and the Ministry of the Interior to disseminate a signal or message, during an event of particular gravity or in a crisis situation (natural and industrial disaster, terrorist attack), to people who are likely to be affected or are in the process of being affected," the ministry said.
Dating back to the Second World War, the sirens of the Réseau National d’Alerte are supposed to sound a warning in the event of a major incident such as a cloud of toxic gas or nuclear accident or other imminent local catastrophe.
An alert signal contains three sequences of 1 minute and 41 seconds, punctuated by five-second silences. The end of alert signal is a continuous sound of 30 seconds.
The Ministry's advice is available here - and includes listening to local radio for further information, as phone lines and internet may be down, and not trying to collect children from school, as they will be cared for by teaching staff.
Read more: Only 1 in 5 knows what siren means
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