New addition for Sirens

Ambulance Siren Uses Vibrations

In Oklahoma, the Emergency Medical Services Authority has equipped one ambulance with a new Howler siren that emits low-frequency tones, as well as sirens, that penetrate objects such as cars with vibrations within 200 feet to alert drivers. According to the Associated Press, EMSA plans to install these sirens on all 77 units in Oklahoma within six months, so if radios are too loud and approaching ambulances aren't heard, they will be felt.
The EMSA told AP that its vehicles have been involved in 16 intersection accidents this year, typically caused by an unyielding driver. Ambulances accounted for all but one of those, EMSA spokeswoman Tina Wells told AP.
"The most frequent thing motorists say to us is they didn't see the ambulance coming," Wells said at a news conference on Nov. 11, where the new technology was demonstrated. During the demonstration, two ambulances (one with and one without the Howler siren) were parked near each other with plastic stepladder with three glasses of liquid in between. The liquids in all three glass rippled when the Howler sounded.
"It's going to make going through intersections much safer," Tulsa Police Officer Mike Avey told AP. "People are on their cell phones, people have $1,000 sound systems. You're going to feel it."
The new sirens cost less than $400 each, meaning the entire EMSA fleet in Oklahoma can be outfitted for less than $40,000.
"A moderate accident is going to cost $15,000 in body damage alone," Wells told AP. "We see the potential for recouping this almost immediately."

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