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Rumbler Rattles Motorists Alert

NCJ Number
Law Enforcement Technology Volume: 35 Issue: 4 Dated: April 2008 Pages: 116,118,119
Rebecca Kanable
Date Published
April 2008
3 pages
This article describes the features and practical uses of the "Rumbler," which can be activated by emergency vehicles to produce sound waves that penetrate and shake solid materials in its vicinity, thus prompting drivers who may not initially see or hear a traditional siren and flashing lights to check their surroundings and thus observe the emergency vehicle approaching.
Loud music, cell phones, air conditioning and heating fans, and perhaps loud children bickering in the backseat may prevent drivers from hearing the siren and seeing the lights of an approaching emergency vehicle on call. The Rumbler attracts attention by creating a vibration. The lower frequency tones of the Rumbler create a shaking motion that allows drivers and nearby pedestrians to feel and not just see and hear the approach of an emergency vehicle. After the Rumbler is activated, the shaking prompts drivers to look into their rearview mirrors to see what is causing the vibration. They can then see the flashing lights of the emergency vehicle. Less than 2 years old, the Rumbler is currently used by approximately 60 law enforcement agencies, with most located in densely populated metropolitan areas on the East Coast. Rumblers are particularly useful at dangerous intersections and in heavy traffic that requires vehicles to move aside to create a path for the emergency vehicle. The Rumbler can cause shaking within approximately 200 feet of a vehicle or intersection. In demonstrations, the vibration captured people's attention but did not jolt or frighten them. In terms of sound, Rumblers operate at 10 decibels, less than the traditional, primary siren. Although a supplemental warning system is an extra cost for law enforcement agencies, in contributing to an avoidance of traffic crashes, it can prevent a costly loss of life and severe injury.