Emergency Alert is the national telephone warning system used to send voice messages to landlines and text messages to mobile phones within a defined area about likely or actual emergencies.

In agreement with Optus and Vodafone, the national Emergency Alert Program has issued advice that current limitations mean 4G mobile phones on the Optus and Vodafone 4G networks may not receive a location based warning. This limitation does not affect Telstra 4G customers.

Vodafone and Optus 4G customers may not receive a warning when they are in an area with 4G coverage on these respective networks.

This also affects customers of mobile phone re-sellers that connect to Optus’ 4G networks, including; Virgin Mobile’s 4G customers and Optus’ wholesale partners who resell the Optus 4G network including iiNet, Internode, Exetel, M2 (consisting of the Dodo, iPrimus and Commander brands), ACN, Blink, SpinTel, Jeenee Mobile, Live Connect and Vaya.

In Tasmania, the issue is limited to locations around metropolitan areas.

However, Tasmanians travelling to the mainland with 4G Vodafone or Optus network dependent mobiles should make themselves aware of the limitations of these services in relation to Emergency Alert.

For more information on how the issue might affect you, check your mobile service provider’s coverage maps and contact your provider for advice on service options.

These options include adjusting the settings on a mobile to switch off the 4G service, the mobile will then revert to 2G and 3G networks, which are fully compatible with Emergency Alert.

The Emergency Alert website (www.emergencyalert.gov.au) has more information on its Frequently Asked Questions pages.

The current 4G limitation on Optus’ and Vodafone’s 4G networks reinforces that members of the public should not rely on receiving a telephone warning before taking action in an emergency.