Your phone stayed silent in the earthquake alert drill. That is normal: settings to check for the real thing

The short answer

In the nationwide Earthquake Early Warning drill on Thursday 5 November (with the test warning scheduled for around 10:00), the test warning was not designed to go to phones as an emergency alert message (the "Area Mail" type of broadcast). If your phone did not sound during the drill, it is not broken and you have not set it up wrongly.

The flip side is that the drill cannot tell you whether your phone will sound for a real warning. The Japan Meteorological Agency says a phone needs two things to receive one: a model that supports the alerts, and the receiving setting switched on. Now that the drill is over, it is a good moment to review phone settings and how people at work will hear about a warning, ready for the next drill or a real one.

What the drill involves, and why phones stay silent

On 29 October the Cabinet Office (disaster management), the Fire and Disaster Management Agency and the Meteorological Agency announced the drill for 5 November, Tsunami Preparedness Day and World Tsunami Awareness Day. The agency sends a test warning at about 10:00; participating organisations relay it through municipal disaster radio, building announcements or dedicated receivers; and participants act to protect themselves. Participants include all prefectures and 1,740 municipalities, 24 national ministries and agencies, and 738 companies and organisations.

The announcement states that the test warning is not relayed on TV, radio or phone emergency alert messages. Some municipalities, however, may broadcast it on cable TV or community FM, or send a test evacuation order or similar by emergency alert message. The agency adds that municipal disaster emails and disaster apps may deliver a warning clearly marked as a drill. If some people at work heard something and others did not, neither is a fault.

Receiving the real alert on your phone

The agency says alerts may not arrive while the phone is in use for communication or where the signal is weak. Phone earthquake warnings use a tone that differs from TV and radio and is the same across carriers. The agency recommends checking in advance what it sounds like.

Apple's support page says that on iPhone, Japan's earthquake and disaster alerts are on by default, and need a SIM or eSIM from a carrier that supports them. You can check them under Settings, then Notifications, at the very bottom. On Android the location depends on the model, so check your maker's or carrier's guidance.

If you use a budget SIM, or two lines in one phone, check whether your provider's guidance says anything about emergency alerts, and ask them if it is unclear.

What to decide at work

If phones are the only way people hear about a warning, anyone on a call or away from their desk is left out. The "Earthquake Early Warning drill action checklist" attached to the announcement lists, as its first item, knowing how you will receive the warning, such as building announcements. If your workplace has no announcement system, agree that whoever's phone sounds first will call out loudly.

The checklist says there are only a few seconds to a few tens of seconds between a warning and strong shaking. There is no time to think then, which is why the point of the drill is to decide in advance what to do in each place. Its examples include not rushing outside, stopping a lift at the nearest floor and getting out, and, when driving, slowing down gradually without braking hard. Workplaces that could not join at the national time can run a drill on another day, for example using the agency's training videos.

Points to watch

The agency warns of spam messages pretending to be earthquake warnings. If you switched off emergency alerts because of too many notifications, cut other notifications instead. Alerts may not arrive where the signal is weak, so combine phones with TV, radio, municipal disaster radio and building announcements.