Emergency information by radio in disasters

A radio station broadcasts its programme from large transmitters. Every radio within range can receive it – no matter how many people are listening at once. That is a big difference from the internet or mobile networks, which quickly reach their limits when overloaded or when the power fails. A receiver also needs little energy, so batteries last a long time.

Civil protection authorities, such as Germany's Federal Office of Civil Protection and Disaster Assistance (BBK), therefore recommend keeping a grid-independent radio at home. In a crisis, many broadcasters work with the authorities and spread warnings and instructions.

A crank radio has a small built-in generator: when you turn the handle, a built-in rechargeable battery is charged. Some models also have a solar cell or can give a phone an emergency top-up. How long the cranking lasts varies greatly from model to model.

The best radio is useless if the batteries are flat or have leaked. Store matching spare batteries and check the radio and batteries at regular intervals, for example when you check your other supplies. Leaking batteries can damage the device; if the instructions recommend it, take them out during long storage.

Write the frequencies of your regional public broadcasters on paper and keep the note with the radio. In an emergency you will not be able to look them up online. Try out beforehand which stations come in well at home – including in the cellar or in the room where you would take shelter in danger.

Do not leave the radio running for hours; listen to the news at set times instead – that saves energy. Follow the authorities' instructions, for example on evacuation, sheltering indoors or help points. Pass important information on to neighbours, especially older people or anyone without a radio.

Rely on official sources: authorities, public or designated broadcasters. In a crisis, rumours spread fast, especially on social media. False news can lead to dangerous decisions, such as driving into a flooded area. If something is unclear, wait for the next official announcement.

Many countries also warn via sirens, warning apps or cell broadcast – warning messages sent directly to all phones in an area. These channels complement the radio but may fail if the network is down.

A broadcast receiver can only receive. If you want to transmit yourself, you need a transmitter – and transmitting is regulated by law. Many radio services require a licence or an exam; amateur radio, for example, generally requires an exam. Other radio uses are licence-free, but only with approved equipment, on certain frequencies and with limited power.

In Europe, for example, there are licence-free handheld radios for short distances (PMR446) that a family or group can use to stay in touch. Which devices, frequencies and transmit powers are allowed differs from country to country. Check the local rules before you buy or use a radio – including devices ordered abroad or online.

When life or health is in danger, the first route is always the local emergency number (112 in the EU). If that does not work, follow the authorities' instructions about help points where you can call for help in a crisis.

Radios exist for different reception types, such as FM, AM (medium wave) or digital radio. Which stations in your region use which channels varies. A device that handles several reception types is more flexible. This entry deliberately lists no frequencies, because they vary by region.

A radio is also useful on the move, for example on longer trips or travels, to hear weather warnings. At home it is best kept in a fixed place with the emergency supplies, together with a lamp, spare batteries and the note with the frequencies. That way you can find it even in the dark.