ALVIN, Texas -- Motorists driving the roads of Alvin can no longer help but notice when an emergency vehicle is coming up from behind. That's because the vehicles are all equipped with a new device called the Rumbler.

It sounds a bit different from a traditional siren and is designed to literally shake vehicles in traffic to let drivers know an emergency vehicle is approaching. Moreover, it can clear an intersection very fast.

“The Rumbler is designed as a secondary siren; it turns on with the horn ring. It is activated by the horn ring and it turns on for 10 seconds,” said Chuck Beettner of Federal Signal Corporation, the makers of the Rumbler.

“I think that's what I am most proud about Alvin, is that we are usually very innovative and we step out there and look at new technology,” said Alvin Police Chief Mike Merkel.

Working with the Florida Highway Patrol, Beettner's company designed the Rumbler to save lives.

In 2007, hundreds of police officers were injured or killed when they collided with drivers who didn't hear or see the patrol cars coming. With soundproof cars, booming car stereo systems and distractions like iPods and mobile phones, the Rumbler could save drivers' lives too.

“The officers absolutely love it,” said Terry Earl, the fleet supervisor for the city of Alvin. “They say the difference that they get when they are trying to clear an intersection is like night and day.”

At a cost of about 400 apiece, Alvin has installed Rumblers on the patrol cars and ambulances, and now the fire department wants them too.

“We're hoping to see a big improvement when we get them installed on our other units,” said Ron Schmitz, the EMS director in Alvin.