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Learn your country's warning signals and alert channels

Sirens, phone alerts and broadcast messages mean different things in different countries. Learn yours now, so everyone knows what to do when one sounds.

How

  1. Find your national warning system on your civil protection agency's website. Note each signal and what it asks you to do.
  2. Sweden example: the air raid warning is short bursts of sound for 1 minute. Go to a shelter or protected space at once. An unbroken 30-second signal means the danger is over.
  3. UK example: Emergency Alerts go to compatible phones and tablets based on where you are now. They make a loud siren-like sound for about 10 seconds, even on silent.
  4. The UK says alerts do not replace local news, radio or TV. Cell broadcast systems such as EU-Alert also need a working mobile network (comms-6).
  5. US example: NOAA Weather Radio and the Emergency Alert System on radio and TV (comms-6).
  6. Write each signal and its meaning on the channel card (comms-3), and practise the response in drills (comms-19).
  7. Trust official sources. Sweden's brochure says to check where information comes from, and not to share it unless you know the source is reliable.

Do these first

Sources

  1. If crisis or war comes (Swedish national brochure, municipal edition, autumn 2024). Swedish Civil Contingencies Agency content, published by Linkoping Municipality, accessed 2026-11
  2. About Emergency Alerts. UK Government (GOV.UK), accessed 2026-11
  3. ETSI TS 102 900: European Public Warning System (EU-ALERT) using the Cell Broadcast Service. ETSI, accessed 2026-11
  4. NOAA Weather Radio All Hazards poster. US National Weather Service, accessed 2026-11
  5. Emergency Alert System fact sheet. FEMA, accessed 2026-11

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