A Rumbler siren is a type of emergency vehicle siren used primarily in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. Developed in 2007 by

Federal Signal Corporation Federal Signal Corporation is an American manufacturer headquartered in Downers Grove, Illinois. Federal Signal manufactures street sweeper vehicles, public address systems, emergency vehicle equipment, and emergency vehicle lighting. The co ...

, and sounding at a low-frequency level, it is designed to be heard by motorists who may otherwise be unable to hear high-frequency sirens due to ambient noise, such as urban traffic.

Design

The Rumbler produces a pulsating, low-frequency sound between 182 and 400 hertz, and is operated in tandem with a standard, piercing high-frequency siren. The lower frequency sound penetrates hard surfaces like glass and doors more effectively than high-frequency tones. In addition, the siren's low-frequency thumping sound also causes noticeable vibrations to drivers and pedestrians who are near it and helps to generate attention in high-noise environments like dense urban traffic. The Rumbler is about 10 decibels quieter than a standard emergency vehicle siren and is generally activated in eight-second bursts by depressing the

horn Horn may refer to: Common uses * Horn (acoustic), a tapered sound guide ** Horn antenna ** Horn loudspeaker ** Vehicle horn ** Train horn *Horn (anatomy), a pointed, bony projection on the head of various animals * Horn (instrument), a family ...

button in a Rumbler-equipped vehicle.

History

The Rumbler was developed by

as an "intersection clearing device". It was initially tested by the

New York Police Department The City of New York Police Department, also referred to as New York City Police Department (NYPD), is the primary law enforcement agency within New York City. Established on May 23, 1845, the NYPD is the largest, and one of the oldest, munic ...

in 2007. According to Noise Off, a

noise pollution Noise pollution, or sound pollution, is the propagation of noise or sound with potential harmful effects on humans and animals. The source of outdoor noise worldwide is mainly caused by machines, transport and propagation systems.Senate Publi ...

advocacy group, more than 100 U.S. police departments had deployed the siren by 2012, including those of:

Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

;

Amarillo, Texas Amarillo ( ; Spanish language, Spanish for "yellow") is a city in the U.S. state of Texas and the county seat of Potter County, Texas, Potter County, though most of the southern half of the city extends into Randall County, Texas, Randall County ...

;

Tulsa, Oklahoma Tulsa ( ) is the List of municipalities in Oklahoma, second-most-populous city in the U.S. state, state of Oklahoma, after Oklahoma City, and the List of United States cities by population, 48th-most-populous city in the United States. The po ...

; and

Reading, Pennsylvania Reading ( ; ) is a city in Berks County, Pennsylvania, United States, and its county seat. The city had a population of 95,112 at the 2020 United States census, 2020 census and is the List of municipalities in Pennsylvania, fourth-most populous ...

. As of 2016, the per-unit cost of the siren was between US$400 and $700 (equivalent to between US$ and $ in ). In 2015, emergency vehicles in

New South Wales, Australia New South Wales (commonly abbreviated as NSW) is a state on the east coast of :Australia. It borders Queensland to the north, Victoria to the south, and South Australia to the west. Its coast borders the Coral and Tasman Seas to the east. T ...

, were outfitted with Rumbler sirens and, the following year, some ambulances in

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

began to be equipped with the Rumbler. According to Singapore officials, the decision to adopt the Rumbler came after seeing its efficacy in U.S. police vehicles.

Wales Air Ambulance The Wales Air Ambulance Charitable Trust (), also known as Wales Air Ambulance Charity (WAAC; , EAAC), is a charity air ambulance service providing a free, life-saving helicopter emergency medical service (HEMS) for the critically ill and inju ...

's response vehicles are now equipped with the rumbler siren. This is the second application of such equipment in the UK, having only previously been used by another response doctor charity in Hampshire. In 2023, more UK police services began to have their cars outfitted with Rumbler sirens, as the siren's low frequency produces a tactile effect that allows drivers to be clearly alerted to the siren's presence, even in modern cars with extensive

soundproofing Soundproofing is any means of impeding sound propagation. There are several methods employed including increasing the distance between the source and receiver, decoupling, using noise barriers to reflect or absorb the energy of the sound waves, ...

which would otherwise block out most of the sound. "Rumbler" was a nominee for "People's Choice Award Word of the Year" for 2016 by the ''

Macquarie Dictionary The ''Macquarie Dictionary'' () is a dictionary of Australian English. It is considered by many to be the standard reference on Australian English. It also pays considerable attention to New Zealand English. Originally it was a publishing proje ...

''. New vehicles operated by the

Queensland Ambulance Service The Queensland Ambulance Service (QAS) is the state emergency ambulance and patient transport provider in Queensland, Australia. QAS is part of the Queensland Government under the Queensland Health portfolio and is one of the largest ambulan ...

are fitted with a Rumbler siren.

References

{{reflist, 1

External links

Long Beach, California police vehicle responding with Rumbler siren (YouTube)

Unmarked New York Police Department vehicle responding with Rumbler siren (YouTube)
Law enforcement equipment Emergency vehicles Sirens

Design

History

See also

References

External links