With the annual Sept. 1 Disaster Prevention Day approaching, residents in Japan will be reminded of a simple fact: They are living in a country where earthquakes are a fact of life.

The reminder is timely. A recent Japan Times online poll showed that only 14 percent of respondents have already set aside a survival kit and know where their local evacuation area is. Of the remaining 86 percent, more than half have done nothing to prepare themselves in the event that the big one finally hits.

Disaster Prevention Day was established in remembrance of the Great Kanto Earthquake of Sept. 1, 1923, at magnitude 7.9 the biggest quake ever known to have struck the Kanto region. More than 100,000 people were killed in the quake and subsequent fires.

Judging from records in this country, the ministry in charge of education and science estimated earlier this year that there is a 30 percent chance of a magnitude 6.7 to 7.2 temblor occurring in the tectonic plates of the southern Kanto region within the next decade, and a 70 percent chance within the next 30 years. Other areas believed to be facing the possibility of a major earthquake in the near future include Shizuoka, Gifu, Yamanashi and Aichi prefectures.

Even with the use of cutting-edge technology, and despite long-term studies by scientists, it is not yet possible to predict the precise date and time that an earthquake will occur. But recent developments have enabled the government to at least issue warnings to people seconds before tremors from a major earthquake reach them.

Starting from Oct. 1, the Meteorological Agency will provide an earthquake warning service (kinkyu jishin sokuho) to the public. Usually an earthquake is preceded by smaller tremors, so the service will warn that major tremors are on the way, based on data from such preliminary tremors.

The agency calculates the magnitude of the earthquake and the location of its focus by analyzing vertical tremors that occur first and are sensed by seismometers at about 1,000 locations across the country. This makes it possible to estimate the size of the major, horizontal tremors that follow and immediately send out warnings.

“If we can catch the preliminary tremors at one location and calculate the focus and size of the earthquake in 5 seconds, we will be able to issue warnings probably in 10 seconds,” said Makoto Saito, senior coordinator for early warnings of earthquakes at the agency. “That means if the major tremors hit certain areas 30 seconds after the preliminary tremors, for instance, that system will make it possible to tell people about the major tremors 20 seconds before.”

In the areas that are close to the focus, major tremors quickly follow preliminary tremors, making it difficult to issue the warnings to these areas in time, according to the agency.

“Some may say this warning service is not good enough because, especially in case of an inland earthquake, the warnings cannot be issued in time to people in the areas nearest to the focus who are most at risk,” Saito said. “But if an earthquake occurs in the sea, there would be some distance between the focus and the areas where people live. The warnings can be given to people before big tremors arrive, though it may give the alert just 10 seconds before. We’ve decided to disclose this information to the public in the hope that it can help reduce the damage caused by the earthquake.”

A preparation time between 10 and 30 seconds can make a huge difference, says Yoshinori Sugihara, of the Japan Electronics and Information Technology Industries Association (JEITA). Sugihara has been in charge of the project there to develop the earthquake warning system.

“If major tremors come suddenly, you will not be able to move. You might not even be able to shelter under a desk. You will not be able to do anything but hang onto your desk,” Sugihara said. “That shows how important the 10-second or 20-second preparation time is, and that’s why this service is significant. School children will be able to shelter under their desks in classrooms if they have about 5 seconds. In fact, it is believed that if we have 10 seconds to prepare for major tremors, we can reduce the number of deaths caused by quakes significantly.”

With the start of the service, the Japan Broadcasting Corporation (NHK) will begin broadcasting the agency’s alert for an earthquake whose tremors would register stronger than 5 on the Japanese intensity scale that goes to 7. NHK will alert areas that could be affected by strong tremors through its television channels and report breaking news on the radio.

At the moment, NHK plans to deliver the warnings only in Japanese, but the public broadcaster will consider providing the information in foreign languages in the future as well, said Kenji Terada, an NHK spokesman. Other TV and radio stations have yet to announce if or when they will start broadcasting the agency’s information.

Mobile-phone companies have developed a system to simultaneously send the agency’s earthquake warnings to users who are in the areas that may be affected by an earthquake whose tremors could register stronger than 4.

By the end of this year, NTT DoCoMo plans to start selling a new cell phone that gives users specially tailored warnings, according to Kaoru Miyamoto, a spokesman for the company. KDDI is also planning to put on the market a cell phone with a similar service, according to the company.

Some companies have introduced a device to receive the agency’s warning service at home. Sun Shine, a Tokyo-based security equipment company, for instance, has developed a home device priced at ¥78,000 called the “EQ Guard.”

Still, JEITA’s Sugihara stresses that the warning system alone is not enough. Checking the quake resistance of your house and knowing the safest spots in your home are among the preparations that people have to make.

“You have to draw up a scenario of what you should do if you hear the warning. Otherwise you cannot take proper action,” he says. “You need to talk with your family about what you should do, such as where to seek shelter, who would look after the elderly and children, and so on.”

Saito of the Meteorological Agency echoes the view.

“This new service is not something that stops earthquakes. You have to prepare for earthquakes in your daily life and think about what you will do when major tremors come,” Saito said. “With that kind of preparation, this earthquake warning service will be used by people effectively.”

Earthquake dos and don’ts

In the event of an earthquake, if you receive a warning from the Meteorological Agency, here is advice from the agency on how to best make use of the new service in the few seconds you have before the tremors arrive.

The Golden Rule: Don’t panic and do take action.

At home: Discuss with your family members or partner in advance about what you should do when you hear the warning.
Protect your head. Keep away from big pieces of furniture that are not secured. Find shelter under sturdy pieces, such as tables or desks. Do not rush outside. If you are in a place where there are any open fires, immediately turn them off or put them out. Open doors to secure a way out of the house after the quake has subsided.

At a large public facility: Follow the instructions of the facility’s staff. Do not rush to the exits. Move away from hanging objects such as lighting equipment.

Outdoors: Keep away from objects which may fall over, such as concrete walls and vending machines, and buildings from which signs or windows may fall.

Driving a car: Do not brake. Go slowly and alert other drivers by turning on your hazard lights. If you feel major tremors, park your car on the side of the road.

On a train or bus: Hold on to a strap tightly.

On an elevator: Stop the elevator at the nearest floor and get off.

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