California professor builds his own home earthquake detector

The issue of earthquakes -- and how to protect both lives and property before, during and after those tremors -- never seems to be too far from the minds of many Californians.

Northern California, for example, is still assessing the damage from last month's 6.0 magnitude Napa earthquake.

The moderately strong quake is being blamed for at least one death, as well as tens of millions of dollars in damage.

On Wednesday, meanwhile, a Nuclear Regulatory Commission official rejected a federal expert's recommendation to shut down Diablo Canyon, California's only operating nuclear power plant, until it can be determined if the facility is truly earthquake-proof.

Diablo Canyon is located near several major earthquake faults, and environmental groups like Friends of the Earth are criticizing Pacific Gas and Electric (PCG), the plant's operator, for putting "safety last and its profits first."

Also this week, a professor at UC Berkeley unveiled a low-cost earthquake detector that, if successful, might eventually make such devices as commonplace as smoke detectors.

Berkeley astronomer Joshua Bloom says his home-made detector cost him about $100 -- and is built from a $35 minicomputer, a speaker, a Wi-Fi adapter and an SD memory card. It also uses Shake Alert, a software developed by researchers at Berkeley's seismology lab, and is linked to earthquake sensors all over California.

"Those sensors wind up shaking and send their signals to a central computer," Bloom told CBS station KPIX 5 -- signals that also broadcast an alert on his home device.

And it apparently works. Bloom says the detector woke him up about five seconds ahead of last month's Napa quake with an automated voice message, saying "Earthquake! Light shaking expected in seconds."

Earthquake early warning systems have made significant advances in recent decades, but are far from being perfected, or available for mainstream use. But Bloom hopes his device might help encourage private and public investing.

"There's a huge safety component to it," he told the Berkeleyside.com news site. "Knowing it's cheap to make will get the public excited and hopefully get the legislature to fund it."