LORTON, Va. (WUSA9) -- Four men trapped under the wreckage left by Nepal's earthquake were saved because of a new, high-tech tool called FINDER.

The device is the size of a small suitcase and uses microwave-radar technology to detect the heartbeats of victims trapped beneath the rubble.

"When you actually see that heartbeat come up on the sensor, at that point, it's an overwhelming feeling of success and relief," said David Lewis, a government contractor.

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In the hard-hit Nepalese village of Chautara, Lewis used FINDER to locate and rescue four men trapped under 10 feet of bricks, mud and other debris.

"And then you can confirm that they're still alive. It's an incredible emotion. Particularly when you go through village after village, house after house and you don't get that response," he said.

The device is the latest life-saving tool in the arsenal of the world's top search and rescue teams. Most already rely on their K9's sense of smell, listening devices in which a victim must be conscious and cameras, which need to be close to anyone who's trapped.

"This device does not need to get that close to them, can shoot through the pile with the radar, sense the heartbeat. The individual does not have to be conscious," said Capt. Randy Bittinger of VA Task Force 1, an elite search and rescue team.

There is nothing, rescuers say, like the expression of a survivor pulled from the rubble.

"It comes through the dirt and the bloodstains and the mud," said Lewis. "Only thing you can see and feel is that expression that they have, that feeling of 'I'm alive.'"

FINDER is so precise, it can even distinguish between the heartbeat of a human and the heartbeat of an animal trapped as much as 30 feet beneath the rubble.

The device was developed by NASA's Jet Propulsion lab and the Department of Homeland Security's Science and Technology division. All four of the men who were rescued in Nepal as the result of the device survived.


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