Japanese gadget can predict tremors before they hit

Using the early-warning system network and data provided by the Japan Meteorological Agency via the Internet, the appliance sounds off a loud countdown of up to 20 seconds before the moment the tremor begins.

Security firm SunShine says this should give people enough time to hide under tables, turn off gas and fire sources, or even just to move away from potentially dangerous furniture.

Starting October, the JMA warnings will also be broadcast on television and radio, and sent to mobile phones equipped to receive them, which will go on sale later this year.

But the company hopes that its EQGuard, which will also be available in October, will help people who just happened not to be watching television.

"There are 51 million households in Japan, and we expect this system to catch on with at least 20 percent of the households," said Kazuo Sasaki, SunShine's president.

Japan accounts for about 20 percent of the world's earthquakes of magnitude 6 or greater.

The appliance sends alerts, once it detects primary waves, or the first waves of an earthquake that do not cause major rattling but travel faster than the secondary waves that are responsible for the actual shaking.

The alerts could precede the shaking by 10 to 20 seconds, though the period would be much shorter--and in some cases absent--if the tremor's center is near.

According the regulatory Electronic Industries Association of Japan, or JEITA, which reviews products, the data from JMA is sometimes wrong and could cause unnecessary panic.

"This system makes mistakes. Its not 100 percent accurate," said Yoshinori Sugihara, head of JEITA's Emergency Earthquake Alert and Trial Project. "The appliance has warned of an earthquake when there was no earthquake."

"But there is value in knowledge before the ground begins shaking. And those that believe this information is more valuable should buy this to save their lives," he added.

Japan started providing earthquake information to emergency personnel, construction sites and train operators last August, but it had put off making the warnings available to the broader public to avoid panic.

An earthquake with a magnitude of 7.3 hit central Japan in 1995, killing more than 6,400 people and causing an estimated $100 billion in damage. In 2004, an earthquake with a magnitude of 6.8 struck the northern prefecture of Niigata, killing about 40 people and injuring more than 3,000.