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Wikipedia

Long-range acoustic device

A long-range acoustic device (LRAD), acoustic hailing device (AHD) or sound cannon is a specialized loudspeaker that produces sound at high power for communicating at a distance. It has been used as a method of crowd control, which has caused permanent hearing damage, having an extremely high decibel capacity (up to 160 dB measured at one meter from the device).[1] Other uses have included for negotiations in siege situations to deal with piracy at sea; for mass notification during natural disasters or other emergencies; and by defense forces, including several navies.

An LRAD on top of a New York City police Hummer
LRAD operator wearing hearing protection
LRAD on a U.S. Navy ship

Overview edit

Acoustic hailing devices are acoustic devices capable of outputting highly intelligible sound at very high volumes. The distance at which acoustic hailing can be effective varies based on several factors including the sound level, directionality, and frequency of the acoustic source, the sensitivity and directionality of the receiver, and the transmission channel environment. The sound level diminishes or attenuates with distance. Consequently, as a general rule, higher source levels have greater range. Acoustic hailing devices can come in two forms;

  1. Directional models: These AHDs are characterized by their ability to create long-range, directional voice communications and warning tones. Their directionality is typically 5° to 60° radius conical at a 2 kHz tone.
  2. Omnidirectional models: These acoustic hailing devices are capable of creating 360° voice communications and warning tones. These devices are capable of being heard over 1.5 miles away from the emitter head.

Origin edit

The term acoustic hailing device came into common use following the suicide attack on the USS Cole while it was at port in Yemen in 2000. Following this attack, the United States Navy established a requirement for an acoustic hailing device. The intent of this AHD was to provide the Navy with a means to establish the intent of an approaching vessel at a distance such that defensive measures could be taken should the vessel not heed a warning. One unique aspect of this requirement was that the sound needed to be focused so that it could be clearly directed at the approaching vessel.

Present edit

Since their inception in 2002, acoustic hailing devices have grown into a variety of applications. AHD uses include checkpoints, crowd control, maritime shipping, mass notification, early warning systems, critical infrastructure protection, military applications and wildlife protection and control. Acoustic hailing devices are now fielded all over the world by various commercial, law enforcement, and military groups.

History edit

In October 2000 the USS Cole, an American guided missile destroyer, was bombed in a terrorist attack by al-Qaeda operatives, using a small boat packed with explosives. The naval personnel on Cole were unable to be sure that their messages could be heard by the approaching boat at a sufficient distance to possibly avert the attack.[2] The ship was badly damaged, 17 U.S. Navy sailors killed and 37 injured.[3]

Following this attack, navies around the world made several policy changes,[2] while the American Technology Corporation (which was rebranded to LRAD Corporation in 2010 and to Genasys in late October 2019[4]) created and developed the AHD market, which included the launch of its proprietary Long Range Acoustic Device, a type of acoustic hailing device, in 2003.[5] Using this new technology, it became possible for naval personnel to contact approaching vessels which did not respond to radio calls from a distance of over 3,000 m (9,800 ft), enabling them to respond appropriately in a timely manner and avert danger.[6]

Since then the technology has developed and expanded. Genasys launched its voice-based mass notification systems in 2012, and in 2019 its unified multichannel Critical Communications and Enterprise Safety system.[5]

LRAD devices have become widely used for communications, and increasingly for crowd control in a range of settings, including civil disturbances and protests.[2]

Characteristics and measurements edit

Acoustic hailing devices differ from conventional speaker systems in three key ways: volume, clarity, and directionality. AHD manufacturers use different methods to measure their products, but a common standard has emerged.

Volume edit

Since sound attenuates with distance, extremely high outputs are required to achieve the required range. Acoustic hailing devices have an output of 135 decibels (dB) or greater. The acoustic level of the source is commonly expressed in terms of Sound Pressure Level or SPL. SPL is a logarithmic measure of the rms sound pressure of a sound relative to a reference value. It is measured in decibels (dB) above a standard reference level. For reference, at a distance of 1 meter, a normal talking voice is approximately 50 dB and a jet engine at 30 meters is 150 dB.

Clarity edit

A principal weakness of common speaker systems and bullhorns is their clarity. Their horns and cones create sound that is distorted or out of phase. This results in the common "Charlie Brown" effect, where the message is muffled and misunderstood, analogous to the muted brass squawks representing the unintelligible voices of adults in animated Peanuts specials. AHDs create sound that is in phase. Because of this, sound emitted from acoustic hailing devices is intelligible at distance. Clarity is difficult to measure, since it is a subjective reference. However, different scales have been created to compare devices. A common measurement is the Speech Transmission Index (STI). STI ratings range from 0–1.0, with 1.0 being perfect clarity.[7]

Focus edit

AHDs are lastly characterized by directionality. To ensure messages are broadcast to the target, AHDs shape sound into a 30–60° audio beam. This shaping is accomplished through the design of the transducers as well as various reflective horns. The focus of an AHD is typically measured at the frequency of peak directionality. This is typically in the 1–2 kHz range. Not all frequencies of sound are able to be directed equally. Lower frequencies in the bass range are difficult to form. As such, their directionality may be a 40 degree radius or more depending on the design of the AHD.


Specifications and functionality edit

LRAD devices are made by Genasys. As of 2022, the company produces a range of LRAD products for mass notification systems. Touting its primary advantage of clarity and intelligibility of voice broadcasts over large distances, its product guide cites the following features:[5]

  • Controlled broadcast dispersion
  • Audible broadcasts feature industry leading clarity and intelligibility
  • 30° audible transmission ranges out to 5,000 meters
  • 60–360° audible mass notification coverage over areas up to 14 km2 (5.4 sq mi)

LRAD products range from hand-held devices to those mounted on helicopters, motor vehicles and ships.[5]

The parameter "ka", which is the wave number multiplied by the speaker radius, is often used to characterize sound source directivity. For this source, ka=19 at 2.5 kHz, and according to the LRAD data sheet, the beam angle of about 30 degrees total is what is predicted for a regular loudspeaker.[8][needs update]

Small spherical "point-source" acoustic devices follow the known inverse square law, which predicts the loss of 6 decibels (dB) per doubling of distance from the source, solely due to geometric spreading. Large speakers (or large arrays), such as these, have an interference pattern in the nearfield which produces peaks 6 dB higher than the output pressure and nulls where the pressure is essentially zero.[9] The larger the speaker, and the higher the frequency, the longer the effective nearfield. The nearfield for this device is approximately 8 metres (26 ft).[9] An LRAD can thus emit a targeted "beam" of sound at very high volume, up to 160 dB at one meter from the device. This is louder than standing behind a jet engine taking off, or a nearby gunshot.[2]

Use edit

Following the impetus for its initial development, 25 navies have adopted the use of LRADs as of 2022, to provide protection for their vessels. Navy personnel can contact approaching vessels from over 3,000 m (9,800 ft) and respond defensively if necessary. They are also used by coast guards, naval bases, commercial vessels, and in ports.[6]

Genasys offers its products for the following categories of use on its U.S. website: defense, law enforcement, fire and rescue services, border security, protection of critical infrastructure, and maritime safety.[10] As of 2022 its products are in use in 100 countries. On the Asia-Pacific website is focused on emergency management during natural disasters such as bushfires.[11] It is not categorized as a defense item, and does not require an export license.[12]

The technology can also be used to deter wildlife from airport runways, as at Changi Airport in Singapore,[13] and to protect gas and oil platforms from fishing boats, birds and security threats.[14][15]

There are two basic ways of using LRAD devices: for voice amplification and as an alert. The technology used in "siren mode" (called an "alert tone" by Genasys[5]), primarily for usage in emergency situations, has also been used for crowd control. In this mode, it allows sound transmission at around 2,000–4,000 Hertz, which causes maximum discomfort for the people targeted, as this is the frequency range at human hearing is most sensitive.[2] Although sometimes referred to as an Active Denial System,[4] the latter is based on a different technology, in which millimetre-wave radiation causes nerve receptors in the skin to feel heat, via dielectric heating.[2]

Risks edit

Acoustic hailing devices have the potential to be used as non-lethal weapons. The human ear can typically stand a sound pressure level of 120 dB before feeling pain. AHDs are capable of 135 dB or more of acoustic energy. The OSHA states that any sound pressure level over 90 dB requires hearing protection.[16] As volume increases so does the chance of hearing loss. The effective non-lethal range of an AHD depends on the total acoustic output of the unit. Typically, this range is 50 meters or less.

In addition to its "voice" feature, which acts as a loudspeaker, the LRAD has an "alert" feature, which emits loud chirping or beeping sounds, which can be used at the top of the decibel range of the device.[4] These sounds have been reported to cause pain and hearing damage.[17] The use of the alert function for crowd control has been described as a "sound cannon" or sonic weapon,[18] although this has been denied by the manufacturer. The sound can be targeted within a narrow and specific range that does not impact those operating the device or standing next to it. Civil liberties organizations are concerned about its use by police forces,[12] and its use has been contested in law courts in the United States. One concern is that police officers are not receiving enough training in its use.[4]

Law enforcement organizations and the manufacturer claim that LRAD systems are primarily designed for long-range communications;[19] however, the device has an extremely high decibel capacity and has been controversially used as a less-lethal weapon for crowd control.[20] Police usually use models that are not quite as powerful as the military-grade version; however, generating levels ranging from 137 dB to 154 dB, they are capable of causing pain, disorientation, nausea, migraines, and permanent damage.[4]

The NYPD's LRAD use was to be challenged in US federal court in 2020.[17][18] Due to potential risks and a lack of studies on the health impact of sonic weapons, the American Civil Liberties Union recommended in a fact sheet that their use in protests be suspended.[21]

Deployments and uses by emergency services edit

Australia edit

By mid-2016, most Australian police forces had acquired LRADs (Queensland Police said that they had been using it since 2009),[22] and concerns were raised about their use for crowd control.[23] However, before 2020, there was no use of the LRAD in public situations; most usage had been by the various police forces for communications during natural disasters or for negotiations with hostage-takers[2][22] in a siege, where it was too dangerous to approach a suspect.[22][23] In June 2020, during the Black Lives Matter protests in New South Wales, NSW Police used LRADs in a different way for the first time,[2] and it has been used at other anti-racism protests in Australia.[24]

The device came to the attention of the wider public when it was used at the 2022 anti-vaccine mandate Canberra protests in "loud hailer" mode for voice messages to be announced to the protesters, and there was speculation among protesters regarding purported harms from its use. However, there was no evidence that it was used as a siren. In addition, some reports appeared to confuse the LRAD with other crowd control devices, such as the Active Denial System;[2] one activist claimed that "supersonic weapons" had been used.[24]

Czech Republic edit

On June 26, 2015, Czech Special Forces Police may have deployed an LRAD 500X during anti-immigration and anti-Islam protests in Brno, the second largest city in the Czech Republic.[25][26]

Police in Prague used a vehicle-mounted LRAD on November 17, 2020, to repeatedly alert protesters on Wenceslas Square to follow COVID restrictions and wear masks.[27] On that day, police supervised several rallies, meetings and demonstrations. Thousands of participants gathered at the largest protests in the Old Town Square. The police and a Prague City Hall representative used an LRAD to repeatedly call upon demonstrators to follow COVID public safety protocols and to comply with security measures.[28]

During a November 25, 2021 march from the center of Prague to the local soccer stadium for a Europa Conference League match, Prague police and regional Czech law enforcement officers utilized vehicle mounted LRADs to broadcast frequent warnings against the use of pyrotechnics by the large crowds.[29]

Prague police officers utilized a vehicle-mounted LRAD to issue more than 500 warnings to revelers not to set off pyrotechnics during downtown December 31, 2021 - January 1, 2022 New Year's Eve celebrations.[30]

A vehicle-mounted LRAD was deployed by police in Prague on March 11, 2023, to communicate to and warn away demonstrators from the National Museum.[31]

Germany edit

in the first half of 2020, Bad Homburg's fire brigade and city police used an LRAD 100X system more than 60 times to deliver COVID-19 information.[32]

Greece edit

Hellenic Police acquired two LRAD systems to be used at the Evros border. These were tested after the March 2020 migrant crisis at the border, triggered by the Turkish government. They are to be used as a deterrent against illegal border entry, as a notification system, as well as to handle aggressive actions against the Hellenic Armed Forces.[33][34]

Japan edit

Japan's Coast Guard used Long Range Acoustic Devices and other methods to expel a North Korean fishing flotilla from its waters in September 2017.[35]

In February 2009, the Japanese whaling fleet operating in Antarctic waters near Australia installed LRADs on their vessels. The device was used against activists of the Sea Shepherd Conservation Society.[36] The Japanese fleet later escalated the use of LRAD, deploying it against a Sea Shepherd helicopter carrying a camera crew.[37][38] Sea Shepherd noted that they had an LRAD of their own, but as of early 2010, had not put it into use[39] other than to play a recording of "Ride of the Valkyries" in the manner of attacking U.S. Army helicopters depicted in the 1979 film Apocalypse Now.[40]

New Zealand edit

During the dispersion of New Zealand's parliament protest in March 2022, LRAD were used by New Zealand police against the protesters. A document released under the Official Information Act (OIA), revealed two long range acoustic devices (LRADs) were deployed at the Parliament protest on March 2.[41] [42]

Poland edit

LRAD was present, but not used because of current legal regulations during protests in Poland, including Million Marijuana March 2011 and Marsz Niepodległości (National Independence Day March) 2011 and 2012. Lacking a way to utilize the LRADs purchased to their full potential sparked an investigation suspecting corruption behind their acquisition. National Police Headquarters spokesman Mariusz Sokolowski defended the purchase of LRAD. He also stressed that the police decided to make this investment because, "We needed good sound reinforcement equipment. With numerous demonstrations and gatherings, police need a public address system that allows you to reach thousands of people."[43]

Municipal police in Gdańsk, Poznań, Kołobrzeg and other cities in Poland used LRAD systems to deliver COVID-19 notifications.[44][45]

Singapore edit

LRAD is used by the Singapore Changi Airport to disperse birds and wildlife from runways.[46]

Spain edit

Local police in Leganés, Spain used a vehicle-mounted LRAD to deliver alerts and notifications to residents during the country-wide COVID-19 lockdown. According to Citizen Security, Communication and local government spokesman, Oscar Oliveira, "Because the acoustic device can be heard inside of houses, we can inform older residents with mobility issues that all municipal resources are available through the Citizen Attention Service by calling 010."[47]

United Kingdom edit

It was confirmed by the Ministry of Defence on May 11, 2012, that an LRAD would be deployed in London during the 2012 Summer Olympic Games. It was spotted fixed to a landing craft on the River Thames.[48]

United States edit

 
An NYPD officer stands ready with the LRAD 500X at an Occupy Wall Street protest on November 17, 2011, near the city hall.

An LRAD was present, but not used, during protests of the 2004 Republican National Convention in New York City.[49][citation needed]

LRADs were used by the Pittsburgh PD during protests at the G20 Summit in September 2009. This was the first time the LRAD was used during a protest in the U.S.[50][51]

LRAD was reportedly used[52] by the Oakland Police Department during the clearance of the Occupy Oakland encampment on the morning of 25 October 2011.

LRAD was present and used when the New York City Police department raided and destroyed the Occupy Wall Street encampment from Zuccotti Park to disrupt and disperse the crowd before arresting or ejecting them on the morning of 15 November 2011.[53][54]

LRAD was deployed during a march against NATO's actions and policies in Chicago on May 20, 2012, at Michigan Ave. & Cermack.[55]

The Salisbury, Maryland Police Department acquired an LRAD in October 2013 with proceeds from their speed cameras.[56]

St. Louis County police used LRAD during protests surrounding the police shooting of Michael Brown in Ferguson, Missouri.[57]

On December 5, 2014, the NYPD utilized an LRAD, notifying approximately 100 protestors to disperse, during the protest of the police killing of Eric Garner in Midtown Manhattan.[58]

Myrtle Beach, South Carolina police obtained two LRAD systems through a federal grant in March 2015. Myrtle Beach police captain Marty Brown told the Myrtle Beach city council that "his department is getting the LRADs to enhance their communication capabilities be it with large crowds or for emergency announcements such as evacuation orders."[59]

The NYPD used a Long Range Acoustic Device during the Baltimore solidarity rally in Union Square on April 29, 2015. An NYPD pickup truck equipped with an LRAD parked near protesters and broadcast a looped warning message about staying off the streets and not blocking the sidewalks.[60]

The New Jersey State Police used an armored-vehicle-mounted LRAD to communicate with crowds denied entry to a June 7, 2015 concert after they began throwing bottles and tried to rush the gates outside MetLife Stadium.[61]

The Greensboro, North Carolina Police Department (GPD) purchased an LRAD 300X and demonstrated it for reporters in November 2015. Jonathan Franks, a GPD captain, said that it could be used for alerts for everything from riots to missing children to weather disasters, and that it could save lives in some cases.[62]

Police in San Diego, California, used an LRAD on May 27, 2016, to order anti-Trump protesters to disperse.[63]

Police from several agencies, including North Dakota state troopers, the National Guard, and other law enforcement agencies from surrounding counties and states deployed two LRADs to clear a protest camp and blockades along Highway 1806. "Long Range Acoustic Devices, which emit an ear-splitting whine, were used intermittently throughout the day" one reporter wrote.[64] An LRAD was present again on November 20, 2016, at the bridge just north of the protesters camp on highway 1806.[citation needed]

The Columbus, Ohio Police Department (CPD) demonstrated a Long Range Acoustic Device to the local media on November 21, 2016. CPD expects to use the device for crowd control, barricaded suspect operations, and to communicate to residents during emergencies and natural disasters.[65]

The Washington, D.C. Metropolitan Police Department used a LRAD at the January 21, 2017 Women's March.[66]

On February 17, 2017, the Princess Anne Police Department deployed its LRAD system at the request of the Maryland State Police to disperse an unruly concert crowd on the campus of the University of Maryland Eastern Shore.[67]

The Mendocino County (California) Board of Supervisors approved the purchase of a Long Range Acoustic Device for the Mendocino County Sheriff's Office on April 18, 2017. Sheriff Tom Allman said the device would aid in searches for missing persons, most often hunters and mushroom pickers, which cost the county tens of thousands of dollars. He said the LRAD might have made the intense 2011 manhunt for Aaron Bassler a little easier, and that it could be used to warn of a tsunami. MCSO found LRAD useful out of a low-flying plane, and it could help in a barricaded-person situation to communicate from the outside of the building.[68]

The Phoenix, Arizona city council approved the purchase of two LRAD 500X systems in November 2018 "to give clear and concise messages to groups of people whenever we find it necessary".[69]

Rochester NY police used verbal warnings and an LRAD to help disperse disorderly crowds during the August 2019 Puerto Rican Festival.[70]

Police utilized a Long Range Acoustic device to declare an unlawful assembly in downtown Phoenix, Arizona, on May 28, 2020, during the George Floyd protests. Multiple announcements were made in English and Spanish.[71]

During the same period, the LRAD was used at a protest in front of the Arkansas State Capitol.[72]

The Portland Police Bureau used a vehicle-mounted LRAD during the protests there following the murder of George Floyd on June 4, 2020, and on other occasions during the protests.[73][74][75]

The Seattle Police Department purchased an LRAD in response to claims that it did not adequately communicate orders to demonstrators during the summer 2020 protests.[76] SPD's use of its LRAD was alleged to have caused ear damage to a peaceful demonstrator, although an internal SPD review deemed the allegations to be unsustained.[77]

A BearCat-mounted LRAD was used to emit voice messages and high-pitched sirens in Kenosha, WI on August 24, 2020, in front of the Kenosha County Courthouse to disperse crowds assembled in Civic Center Park as part of the Jacob Blake protests.[78][79][80]

Rochester, NY police used a Long Range Acoustic Device to make announcements to protesters that they were unlawfully in the roadway and obstructing traffic on September 12, 2020. The device was also used at the September 16, 2020 protest in front of Rochester city hall.[81][82]

In September 2020, it was revealed that federal officials had explored the use of the device and the Active Denial System ("heat ray") to disperse civilians protesting outside the White House in June of that year, but had been advised that the National Guard was not currently in possession of either device.[83]

Protesters at the June 1, 2020 Washington, D.C. George Floyd protests said police gave little or no warning before employing aggressive tactics against them. A 2015 settlement requires federal police to give large crowds several loud dispersal orders before deploying chemical irritants and other dispersion tools. Using an LRAD to issue loud protest dispersal orders would have complied with the 2015 settlement requirement.[84][85]

The Cuyahoga County Sheriff's Department purchased Long Range Acoustic Devices to improve the department's ability to issue dispersal orders clearly over long distances. The purchases resulted from the department's after-action report of the May 30, 2020 riot in downtown Cleveland.[86]

After receiving feedback from protesters who said commands from on-scene officers were not clear or loud enough, the Seattle, WA mayor's office recommended purchasing an LRAD.[87]

On March 6, 2021, the Boulder Police Department used a toned warble noise from an LRAD in an effort to disperse a crowd of up to 800 students from the University of Colorado Boulder. The University Hill Incident occurred when code enforcement and members of Boulder Police's Neighborhood Impact Team were unable to disperse partygoers who were congregating against Boulders public health order. LRAD was used after students and other partygoers began throwing rocks at SWAT vehicles and officers.[88]

On April 12, 2021, the Brooklyn Center, MN Police Department deployed a vehicle mounted LRAD outside of its headquarters to announce curfew violations and dispersal orders to a large crowd protesting the death of Daunte Wright.[89]

On July 3, 2021, Massachusetts State Police utilized an LRAD to secure a group[clarification needed] of 11 suspects involved in the Sovereign Citizen movement. The group identified themselves as part of the "Rise of the Moors" movement, or "Moorish Americans". The self styled militia group was traveling between Rhode Island and Maine when an MSP trooper came across their convoy refueling. The group had multiple firearms in their possession, and admitted to not having proper carrying requirements. Several fled into the surrounding forest, at which point the LRAD was deployed. The group was taken into custody without further incident.[90]

The Oklahoma County, Oklahoma Sheriff's Office Tactical Team used a vehicle-mounted LRAD on November 22, 2021, to serve a search warrant on a residence suspected of being used for drug trafficking.[91]

The Charlotte-Mecklenburg, North Carolina Police Department Crisis Intervention Team and SWAT negotiators used a long-range acoustic device to talk a man down from an energized electrical tower.[92]

Mass notification edit

Australia edit

Genasys has supplied its NEWS mass notification service in Australia since 2013, when it partnered with Nokia to deliver emergency notifications via SMS, following the disastrous consequences of the Black Saturday bushfires in 2009.[11]

United States edit

Menlo Park and Atherton, California police and fire officials attended a 'sound off' between a siren installation and an LRAD 360XT mobile voice mass notification system in April 2018. "The side by side test was very helpful and everyone agreed that the LRAD system completely outperformed the older siren system," said Fire District Emergency Manager Ryan Zollicoffer. "Not only because of the voice capability, but the modular-mobility benefit is something that appeals to first responders because it can be used for a variety of public safety purposes and better moved around if that's needed or desired."[93]

The Menlo Park Fire District demonstrated its Long Range Acoustic Device (LRAD) community notification system on April 18, 2019. The fire district also showed how the ShakeAlert system could eventually be tied together with its LRAD to provide area wide audible alerts for earthquake, flood, fire and other emergencies. "ShakeAlert will notify and protect our Station firefighters, but we also believe coupled with the LRAD public address system, it can help to bridge the 'notification gap' as another important public safety tool and option for community early warning messaging for earthquakes as well as for fire and flooding information and evacuation signaling," said Fire Chief Harold Schapelhouman.[94]

The City of Laguna Beach, California, installed LRAD speaker sirens in 2018. The systems alert the downtown and Main Beach areas during an emergency where the public needs to take immediate action.[95]

In June 2019, Mill Valley, California, became the first city in the Bay Area to replace its sirens with LRAD community notification systems. The combined siren loudspeakers receive emergency messages via satellite and have backup batteries if the power fails.[96]

The Mill Valley Fire Department began testing its city's new LRAD installations on June 27, 2019. LRAD systems project both siren and voice recordings to alert and inform community members during large-scale disasters. The Long Range Acoustic Devices replaced siren-only systems in five Mill Valley, California locations. "We believe that the purchase and installation of LRAD goes a long way to improve the resiliency and redundancy of our communication systems," Mill Valley Fire Chief Tom Welch said. "LRAD systems are highly effective in communicating warnings, instructions, and notifications throughout incident sites and over vast areas during life-threatening events."[97]

The City of Newport Beach plans to spend $200,000 to replace three rusty tsunami warning sirens on the Balboa Peninsula with LRAD siren/public address systems. The LRAD systems are expected to be installed by the end of 2019.[98]

In October 2020, Laguna Beach, California, tested its expanded outdoor warning system of 13 Long Range Acoustic Devices mounted on buildings throughout the city. The solar-powered devices broadcast recorded evacuation messages in case cell service is disabled during a disaster.[99]

Seven new LRAD emergency siren systems are scheduled for installation in southern Marin County in 2022.[100]

The Berkeley, California city council approved the installation of a Genasys outdoor warning system to alert residents of fires, earthquakes, tsunamis and other disasters. The system is capable of running on solar-powered battery backup and being controlled remotely via satellite.[101]

Public safety officials in Berkeley, California unveiled the city's new Genasys emergency warning network during the September 17, 2023 Fire Ready Fest. Ten systems that broadcast both sirens and voice messages have been installed on buildings throughout Berkeley to provide another layer of reaching residents and visitors in the event of serious emergencies. Five more systems are projected to be installed by early 2024.[102]

High seas anti-piracy edit

 
LRAD on RMS Queen Mary 2

On November 5, 2005, the luxury cruise ship Seabourn Spirit employed an LRAD to repel pirates who attacked the vessel with rocket-propelled grenades about 115 km off the coast of Somalia.[103] The effectiveness of this device during the attack is not completely clear, but the pirates did not succeed in boarding the vessel and eventually fled.

The Liberian-flagged vessel MV Biscaglia was attacked on November 28, 2008. The security detachment aboard Biscaglia was reported to have used an LRAD device in an effort to repel attackers armed with assault rifles and rocket-propelled grenades. Following a one-sided shootout, the ship was seized and the unarmed security contractors abandoned ship leaving the ship and crew to the pirates.[104] The incident caused the usefulness of LRADs to be called into question by Lloyd's List.[105] The security detachment's reported use of LRAD is not completely clear as The Wall Street Journal makes no mention of LRAD being used during the incident.[106]

In January 2011, the Spirit of Adventure, a cruise ship sailing through the Indian Ocean, deployed an LRAD system as part of its defensive measures when being pursued by pirates.[107]

S/Y Hideaway used an LRAD in 2016 to deter suspected pirates in the Gulf of Aden.[108]

Major users edit

See also edit

References edit

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  6. ^ a b "Maritime Community & Safety". Genasys Inc. October 7, 2020. Retrieved February 23, 2022.
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  11. ^ a b "The Critical Communications Company". Genasys APAC. Retrieved February 23, 2022.
  12. ^ a b Sindelar, Daisy (March 13, 2013). "Explainer: LRAD -- What Is It And How Does It Work?". RadioFreeEurope/RadioLiberty. Retrieved February 23, 2022.
  13. ^ Tan, Yvette (October 29, 2021). "Lasers and giant speakers: How airports chase birds off the runway". Mashable. Retrieved February 23, 2022.
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  16. ^ "1910.95 - Occupational noise exposure. | Occupational Safety and Health Administration".
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  25. ^ . Archived from the original on June 29, 2015. Retrieved June 27, 2015.{{cite web}}: CS1 maint: archived copy as title (link)
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External links edit

long, range, acoustic, device, lrad, redirects, here, dance, qualification, licentiate, royal, academy, dance, long, range, acoustic, device, lrad, acoustic, hailing, device, sound, cannon, specialized, loudspeaker, that, produces, sound, high, power, communic. LRAD redirects here For the dance qualification see Licentiate of the Royal Academy of Dance A long range acoustic device LRAD acoustic hailing device AHD or sound cannon is a specialized loudspeaker that produces sound at high power for communicating at a distance It has been used as a method of crowd control which has caused permanent hearing damage having an extremely high decibel capacity up to 160 dB measured at one meter from the device 1 Other uses have included for negotiations in siege situations to deal with piracy at sea for mass notification during natural disasters or other emergencies and by defense forces including several navies An LRAD on top of a New York City police HummerLRAD operator wearing hearing protectionLRAD on a U S Navy ship Contents 1 Overview 1 1 Origin 1 2 Present 2 History 3 Characteristics and measurements 3 1 Volume 3 2 Clarity 3 3 Focus 4 Specifications and functionality 5 Use 6 Risks 7 Deployments and uses by emergency services 7 1 Australia 7 2 Czech Republic 7 3 Germany 7 4 Greece 7 5 Japan 7 6 New Zealand 7 7 Poland 7 8 Singapore 7 9 Spain 7 10 United Kingdom 7 11 United States 8 Mass notification 8 1 Australia 8 2 United States 9 High seas anti piracy 10 Major users 11 See also 12 References 13 External linksOverview editAcoustic hailing devices are acoustic devices capable of outputting highly intelligible sound at very high volumes The distance at which acoustic hailing can be effective varies based on several factors including the sound level directionality and frequency of the acoustic source the sensitivity and directionality of the receiver and the transmission channel environment The sound level diminishes or attenuates with distance Consequently as a general rule higher source levels have greater range Acoustic hailing devices can come in two forms Directional models These AHDs are characterized by their ability to create long range directional voice communications and warning tones Their directionality is typically 5 to 60 radius conical at a 2 kHz tone Omnidirectional models These acoustic hailing devices are capable of creating 360 voice communications and warning tones These devices are capable of being heard over 1 5 miles away from the emitter head Origin edit The term acoustic hailing device came into common use following the suicide attack on the USS Cole while it was at port in Yemen in 2000 Following this attack the United States Navy established a requirement for an acoustic hailing device The intent of this AHD was to provide the Navy with a means to establish the intent of an approaching vessel at a distance such that defensive measures could be taken should the vessel not heed a warning One unique aspect of this requirement was that the sound needed to be focused so that it could be clearly directed at the approaching vessel Present edit Since their inception in 2002 acoustic hailing devices have grown into a variety of applications AHD uses include checkpoints crowd control maritime shipping mass notification early warning systems critical infrastructure protection military applications and wildlife protection and control Acoustic hailing devices are now fielded all over the world by various commercial law enforcement and military groups History editIn October 2000 the USS Cole an American guided missile destroyer was bombed in a terrorist attack by al Qaeda operatives using a small boat packed with explosives The naval personnel on Cole were unable to be sure that their messages could be heard by the approaching boat at a sufficient distance to possibly avert the attack 2 The ship was badly damaged 17 U S Navy sailors killed and 37 injured 3 Following this attack navies around the world made several policy changes 2 while the American Technology Corporation which was rebranded to LRAD Corporation in 2010 and to Genasys in late October 2019 4 created and developed the AHD market which included the launch of its proprietary Long Range Acoustic Device a type of acoustic hailing device in 2003 5 Using this new technology it became possible for naval personnel to contact approaching vessels which did not respond to radio calls from a distance of over 3 000 m 9 800 ft enabling them to respond appropriately in a timely manner and avert danger 6 Since then the technology has developed and expanded Genasys launched its voice based mass notification systems in 2012 and in 2019 its unified multichannel Critical Communications and Enterprise Safety system 5 LRAD devices have become widely used for communications and increasingly for crowd control in a range of settings including civil disturbances and protests 2 Characteristics and measurements editAcoustic hailing devices differ from conventional speaker systems in three key ways volume clarity and directionality AHD manufacturers use different methods to measure their products but a common standard has emerged Volume edit Since sound attenuates with distance extremely high outputs are required to achieve the required range Acoustic hailing devices have an output of 135 decibels dB or greater The acoustic level of the source is commonly expressed in terms of Sound Pressure Level or SPL SPL is a logarithmic measure of the rms sound pressure of a sound relative to a reference value It is measured in decibels dB above a standard reference level For reference at a distance of 1 meter a normal talking voice is approximately 50 dB and a jet engine at 30 meters is 150 dB Clarity edit A principal weakness of common speaker systems and bullhorns is their clarity Their horns and cones create sound that is distorted or out of phase This results in the common Charlie Brown effect where the message is muffled and misunderstood analogous to the muted brass squawks representing the unintelligible voices of adults in animated Peanuts specials AHDs create sound that is in phase Because of this sound emitted from acoustic hailing devices is intelligible at distance Clarity is difficult to measure since it is a subjective reference However different scales have been created to compare devices A common measurement is the Speech Transmission Index STI STI ratings range from 0 1 0 with 1 0 being perfect clarity 7 Focus edit AHDs are lastly characterized by directionality To ensure messages are broadcast to the target AHDs shape sound into a 30 60 audio beam This shaping is accomplished through the design of the transducers as well as various reflective horns The focus of an AHD is typically measured at the frequency of peak directionality This is typically in the 1 2 kHz range Not all frequencies of sound are able to be directed equally Lower frequencies in the bass range are difficult to form As such their directionality may be a 40 degree radius or more depending on the design of the AHD Specifications and functionality editLRAD devices are made by Genasys As of 2022 update the company produces a range of LRAD products for mass notification systems Touting its primary advantage of clarity and intelligibility of voice broadcasts over large distances its product guide cites the following features 5 Controlled broadcast dispersion Audible broadcasts feature industry leading clarity and intelligibility 30 audible transmission ranges out to 5 000 meters 60 360 audible mass notification coverage over areas up to 14 km2 5 4 sq mi LRAD products range from hand held devices to those mounted on helicopters motor vehicles and ships 5 The parameter ka which is the wave number multiplied by the speaker radius is often used to characterize sound source directivity For this source ka 19 at 2 5 kHz and according to the LRAD data sheet the beam angle of about 30 degrees total is what is predicted for a regular loudspeaker 8 needs update Small spherical point source acoustic devices follow the known inverse square law which predicts the loss of 6 decibels dB per doubling of distance from the source solely due to geometric spreading Large speakers or large arrays such as these have an interference pattern in the nearfield which produces peaks 6 dB higher than the output pressure and nulls where the pressure is essentially zero 9 The larger the speaker and the higher the frequency the longer the effective nearfield The nearfield for this device is approximately 8 metres 26 ft 9 An LRAD can thus emit a targeted beam of sound at very high volume up to 160 dB at one meter from the device This is louder than standing behind a jet engine taking off or a nearby gunshot 2 Use editFollowing the impetus for its initial development 25 navies have adopted the use of LRADs as of 2022 update to provide protection for their vessels Navy personnel can contact approaching vessels from over 3 000 m 9 800 ft and respond defensively if necessary They are also used by coast guards naval bases commercial vessels and in ports 6 Genasys offers its products for the following categories of use on its U S website defense law enforcement fire and rescue services border security protection of critical infrastructure and maritime safety 10 As of 2022 update its products are in use in 100 countries On the Asia Pacific website is focused on emergency management during natural disasters such as bushfires 11 It is not categorized as a defense item and does not require an export license 12 The technology can also be used to deter wildlife from airport runways as at Changi Airport in Singapore 13 and to protect gas and oil platforms from fishing boats birds and security threats 14 15 There are two basic ways of using LRAD devices for voice amplification and as an alert The technology used in siren mode called an alert tone by Genasys 5 primarily for usage in emergency situations has also been used for crowd control In this mode it allows sound transmission at around 2 000 4 000 Hertz which causes maximum discomfort for the people targeted as this is the frequency range at human hearing is most sensitive 2 Although sometimes referred to as an Active Denial System 4 the latter is based on a different technology in which millimetre wave radiation causes nerve receptors in the skin to feel heat via dielectric heating 2 Risks editAcoustic hailing devices have the potential to be used as non lethal weapons The human ear can typically stand a sound pressure level of 120 dB before feeling pain AHDs are capable of 135 dB or more of acoustic energy The OSHA states that any sound pressure level over 90 dB requires hearing protection 16 As volume increases so does the chance of hearing loss The effective non lethal range of an AHD depends on the total acoustic output of the unit Typically this range is 50 meters or less In addition to its voice feature which acts as a loudspeaker the LRAD has an alert feature which emits loud chirping or beeping sounds which can be used at the top of the decibel range of the device 4 These sounds have been reported to cause pain and hearing damage 17 The use of the alert function for crowd control has been described as a sound cannon or sonic weapon 18 although this has been denied by the manufacturer The sound can be targeted within a narrow and specific range that does not impact those operating the device or standing next to it Civil liberties organizations are concerned about its use by police forces 12 and its use has been contested in law courts in the United States One concern is that police officers are not receiving enough training in its use 4 Law enforcement organizations and the manufacturer claim that LRAD systems are primarily designed for long range communications 19 however the device has an extremely high decibel capacity and has been controversially used as a less lethal weapon for crowd control 20 Police usually use models that are not quite as powerful as the military grade version however generating levels ranging from 137 dB to 154 dB they are capable of causing pain disorientation nausea migraines and permanent damage 4 The NYPD s LRAD use was to be challenged in US federal court in 2020 17 18 Due to potential risks and a lack of studies on the health impact of sonic weapons the American Civil Liberties Union recommended in a fact sheet that their use in protests be suspended 21 Deployments and uses by emergency services editThis section may contain excessive or irrelevant examples Please help improve the article by adding descriptive text and removing less pertinent examples April 2022 Australia edit By mid 2016 most Australian police forces had acquired LRADs Queensland Police said that they had been using it since 2009 22 and concerns were raised about their use for crowd control 23 However before 2020 there was no use of the LRAD in public situations most usage had been by the various police forces for communications during natural disasters or for negotiations with hostage takers 2 22 in a siege where it was too dangerous to approach a suspect 22 23 In June 2020 during the Black Lives Matter protests in New South Wales NSW Police used LRADs in a different way for the first time 2 and it has been used at other anti racism protests in Australia 24 The device came to the attention of the wider public when it was used at the 2022 anti vaccine mandate Canberra protests in loud hailer mode for voice messages to be announced to the protesters and there was speculation among protesters regarding purported harms from its use However there was no evidence that it was used as a siren In addition some reports appeared to confuse the LRAD with other crowd control devices such as the Active Denial System 2 one activist claimed that supersonic weapons had been used 24 Czech Republic edit On June 26 2015 Czech Special Forces Police may have deployed an LRAD 500X during anti immigration and anti Islam protests in Brno the second largest city in the Czech Republic 25 26 Police in Prague used a vehicle mounted LRAD on November 17 2020 to repeatedly alert protesters on Wenceslas Square to follow COVID restrictions and wear masks 27 On that day police supervised several rallies meetings and demonstrations Thousands of participants gathered at the largest protests in the Old Town Square The police and a Prague City Hall representative used an LRAD to repeatedly call upon demonstrators to follow COVID public safety protocols and to comply with security measures 28 During a November 25 2021 march from the center of Prague to the local soccer stadium for a Europa Conference League match Prague police and regional Czech law enforcement officers utilized vehicle mounted LRADs to broadcast frequent warnings against the use of pyrotechnics by the large crowds 29 Prague police officers utilized a vehicle mounted LRAD to issue more than 500 warnings to revelers not to set off pyrotechnics during downtown December 31 2021 January 1 2022 New Year s Eve celebrations 30 A vehicle mounted LRAD was deployed by police in Prague on March 11 2023 to communicate to and warn away demonstrators from the National Museum 31 Germany edit in the first half of 2020 Bad Homburg s fire brigade and city police used an LRAD 100X system more than 60 times to deliver COVID 19 information 32 Greece edit Hellenic Police acquired two LRAD systems to be used at the Evros border These were tested after the March 2020 migrant crisis at the border triggered by the Turkish government They are to be used as a deterrent against illegal border entry as a notification system as well as to handle aggressive actions against the Hellenic Armed Forces 33 34 Japan edit Japan s Coast Guard used Long Range Acoustic Devices and other methods to expel a North Korean fishing flotilla from its waters in September 2017 35 In February 2009 the Japanese whaling fleet operating in Antarctic waters near Australia installed LRADs on their vessels The device was used against activists of the Sea Shepherd Conservation Society 36 The Japanese fleet later escalated the use of LRAD deploying it against a Sea Shepherd helicopter carrying a camera crew 37 38 Sea Shepherd noted that they had an LRAD of their own but as of early 2010 had not put it into use 39 other than to play a recording of Ride of the Valkyries in the manner of attacking U S Army helicopters depicted in the 1979 film Apocalypse Now 40 New Zealand edit During the dispersion of New Zealand s parliament protest in March 2022 LRAD were used by New Zealand police against the protesters A document released under the Official Information Act OIA revealed two long range acoustic devices LRADs were deployed at the Parliament protest on March 2 41 42 Poland edit LRAD was present but not used because of current legal regulations during protests in Poland including Million Marijuana March 2011 and Marsz Niepodleglosci National Independence Day March 2011 and 2012 Lacking a way to utilize the LRADs purchased to their full potential sparked an investigation suspecting corruption behind their acquisition National Police Headquarters spokesman Mariusz Sokolowski defended the purchase of LRAD He also stressed that the police decided to make this investment because We needed good sound reinforcement equipment With numerous demonstrations and gatherings police need a public address system that allows you to reach thousands of people 43 Municipal police in Gdansk Poznan Kolobrzeg and other cities in Poland used LRAD systems to deliver COVID 19 notifications 44 45 Singapore edit LRAD is used by the Singapore Changi Airport to disperse birds and wildlife from runways 46 Spain edit Local police in Leganes Spain used a vehicle mounted LRAD to deliver alerts and notifications to residents during the country wide COVID 19 lockdown According to Citizen Security Communication and local government spokesman Oscar Oliveira Because the acoustic device can be heard inside of houses we can inform older residents with mobility issues that all municipal resources are available through the Citizen Attention Service by calling 010 47 United Kingdom edit It was confirmed by the Ministry of Defence on May 11 2012 that an LRAD would be deployed in London during the 2012 Summer Olympic Games It was spotted fixed to a landing craft on the River Thames 48 United States edit nbsp An NYPD officer stands ready with the LRAD 500X at an Occupy Wall Street protest on November 17 2011 near the city hall An LRAD was present but not used during protests of the 2004 Republican National Convention in New York City 49 citation needed LRADs were used by the Pittsburgh PD during protests at the G20 Summit in September 2009 This was the first time the LRAD was used during a protest in the U S 50 51 LRAD was reportedly used 52 by the Oakland Police Department during the clearance of the Occupy Oakland encampment on the morning of 25 October 2011 LRAD was present and used when the New York City Police department raided and destroyed the Occupy Wall Street encampment from Zuccotti Park to disrupt and disperse the crowd before arresting or ejecting them on the morning of 15 November 2011 53 54 LRAD was deployed during a march against NATO s actions and policies in Chicago on May 20 2012 at Michigan Ave amp Cermack 55 The Salisbury Maryland Police Department acquired an LRAD in October 2013 with proceeds from their speed cameras 56 St Louis County police used LRAD during protests surrounding the police shooting of Michael Brown in Ferguson Missouri 57 On December 5 2014 the NYPD utilized an LRAD notifying approximately 100 protestors to disperse during the protest of the police killing of Eric Garner in Midtown Manhattan 58 Myrtle Beach South Carolina police obtained two LRAD systems through a federal grant in March 2015 Myrtle Beach police captain Marty Brown told the Myrtle Beach city council that his department is getting the LRADs to enhance their communication capabilities be it with large crowds or for emergency announcements such as evacuation orders 59 The NYPD used a Long Range Acoustic Device during the Baltimore solidarity rally in Union Square on April 29 2015 An NYPD pickup truck equipped with an LRAD parked near protesters and broadcast a looped warning message about staying off the streets and not blocking the sidewalks 60 The New Jersey State Police used an armored vehicle mounted LRAD to communicate with crowds denied entry to a June 7 2015 concert after they began throwing bottles and tried to rush the gates outside MetLife Stadium 61 The Greensboro North Carolina Police Department GPD purchased an LRAD 300X and demonstrated it for reporters in November 2015 Jonathan Franks a GPD captain said that it could be used for alerts for everything from riots to missing children to weather disasters and that it could save lives in some cases 62 Police in San Diego California used an LRAD on May 27 2016 to order anti Trump protesters to disperse 63 Police from several agencies including North Dakota state troopers the National Guard and other law enforcement agencies from surrounding counties and states deployed two LRADs to clear a protest camp and blockades along Highway 1806 Long Range Acoustic Devices which emit an ear splitting whine were used intermittently throughout the day one reporter wrote 64 An LRAD was present again on November 20 2016 at the bridge just north of the protesters camp on highway 1806 citation needed The Columbus Ohio Police Department CPD demonstrated a Long Range Acoustic Device to the local media on November 21 2016 CPD expects to use the device for crowd control barricaded suspect operations and to communicate to residents during emergencies and natural disasters 65 The Washington D C Metropolitan Police Department used a LRAD at the January 21 2017 Women s March 66 On February 17 2017 the Princess Anne Police Department deployed its LRAD system at the request of the Maryland State Police to disperse an unruly concert crowd on the campus of the University of Maryland Eastern Shore 67 The Mendocino County California Board of Supervisors approved the purchase of a Long Range Acoustic Device for the Mendocino County Sheriff s Office on April 18 2017 Sheriff Tom Allman said the device would aid in searches for missing persons most often hunters and mushroom pickers which cost the county tens of thousands of dollars He said the LRAD might have made the intense 2011 manhunt for Aaron Bassler a little easier and that it could be used to warn of a tsunami MCSO found LRAD useful out of a low flying plane and it could help in a barricaded person situation to communicate from the outside of the building 68 The Phoenix Arizona city council approved the purchase of two LRAD 500X systems in November 2018 to give clear and concise messages to groups of people whenever we find it necessary 69 Rochester NY police used verbal warnings and an LRAD to help disperse disorderly crowds during the August 2019 Puerto Rican Festival 70 Police utilized a Long Range Acoustic device to declare an unlawful assembly in downtown Phoenix Arizona on May 28 2020 during the George Floyd protests Multiple announcements were made in English and Spanish 71 During the same period the LRAD was used at a protest in front of the Arkansas State Capitol 72 The Portland Police Bureau used a vehicle mounted LRAD during the protests there following the murder of George Floyd on June 4 2020 and on other occasions during the protests 73 74 75 The Seattle Police Department purchased an LRAD in response to claims that it did not adequately communicate orders to demonstrators during the summer 2020 protests 76 SPD s use of its LRAD was alleged to have caused ear damage to a peaceful demonstrator although an internal SPD review deemed the allegations to be unsustained 77 A BearCat mounted LRAD was used to emit voice messages and high pitched sirens in Kenosha WI on August 24 2020 in front of the Kenosha County Courthouse to disperse crowds assembled in Civic Center Park as part of the Jacob Blake protests 78 79 80 Rochester NY police used a Long Range Acoustic Device to make announcements to protesters that they were unlawfully in the roadway and obstructing traffic on September 12 2020 The device was also used at the September 16 2020 protest in front of Rochester city hall 81 82 In September 2020 it was revealed that federal officials had explored the use of the device and the Active Denial System heat ray to disperse civilians protesting outside the White House in June of that year but had been advised that the National Guard was not currently in possession of either device 83 Protesters at the June 1 2020 Washington D C George Floyd protests said police gave little or no warning before employing aggressive tactics against them A 2015 settlement requires federal police to give large crowds several loud dispersal orders before deploying chemical irritants and other dispersion tools Using an LRAD to issue loud protest dispersal orders would have complied with the 2015 settlement requirement 84 85 The Cuyahoga County Sheriff s Department purchased Long Range Acoustic Devices to improve the department s ability to issue dispersal orders clearly over long distances The purchases resulted from the department s after action report of the May 30 2020 riot in downtown Cleveland 86 After receiving feedback from protesters who said commands from on scene officers were not clear or loud enough the Seattle WA mayor s office recommended purchasing an LRAD 87 On March 6 2021 the Boulder Police Department used a toned warble noise from an LRAD in an effort to disperse a crowd of up to 800 students from the University of Colorado Boulder The University Hill Incident occurred when code enforcement and members of Boulder Police s Neighborhood Impact Team were unable to disperse partygoers who were congregating against Boulders public health order LRAD was used after students and other partygoers began throwing rocks at SWAT vehicles and officers 88 On April 12 2021 the Brooklyn Center MN Police Department deployed a vehicle mounted LRAD outside of its headquarters to announce curfew violations and dispersal orders to a large crowd protesting the death of Daunte Wright 89 On July 3 2021 Massachusetts State Police utilized an LRAD to secure a group clarification needed of 11 suspects involved in the Sovereign Citizen movement The group identified themselves as part of the Rise of the Moors movement or Moorish Americans The self styled militia group was traveling between Rhode Island and Maine when an MSP trooper came across their convoy refueling The group had multiple firearms in their possession and admitted to not having proper carrying requirements Several fled into the surrounding forest at which point the LRAD was deployed The group was taken into custody without further incident 90 The Oklahoma County Oklahoma Sheriff s Office Tactical Team used a vehicle mounted LRAD on November 22 2021 to serve a search warrant on a residence suspected of being used for drug trafficking 91 The Charlotte Mecklenburg North Carolina Police Department Crisis Intervention Team and SWAT negotiators used a long range acoustic device to talk a man down from an energized electrical tower 92 Mass notification editAustralia edit Genasys has supplied its NEWS mass notification service in Australia since 2013 when it partnered with Nokia to deliver emergency notifications via SMS following the disastrous consequences of the Black Saturday bushfires in 2009 11 United States edit Menlo Park and Atherton California police and fire officials attended a sound off between a siren installation and an LRAD 360XT mobile voice mass notification system in April 2018 The side by side test was very helpful and everyone agreed that the LRAD system completely outperformed the older siren system said Fire District Emergency Manager Ryan Zollicoffer Not only because of the voice capability but the modular mobility benefit is something that appeals to first responders because it can be used for a variety of public safety purposes and better moved around if that s needed or desired 93 The Menlo Park Fire District demonstrated its Long Range Acoustic Device LRAD community notification system on April 18 2019 The fire district also showed how the ShakeAlert system could eventually be tied together with its LRAD to provide area wide audible alerts for earthquake flood fire and other emergencies ShakeAlert will notify and protect our Station firefighters but we also believe coupled with the LRAD public address system it can help to bridge the notification gap as another important public safety tool and option for community early warning messaging for earthquakes as well as for fire and flooding information and evacuation signaling said Fire Chief Harold Schapelhouman 94 The City of Laguna Beach California installed LRAD speaker sirens in 2018 The systems alert the downtown and Main Beach areas during an emergency where the public needs to take immediate action 95 In June 2019 Mill Valley California became the first city in the Bay Area to replace its sirens with LRAD community notification systems The combined siren loudspeakers receive emergency messages via satellite and have backup batteries if the power fails 96 The Mill Valley Fire Department began testing its city s new LRAD installations on June 27 2019 LRAD systems project both siren and voice recordings to alert and inform community members during large scale disasters The Long Range Acoustic Devices replaced siren only systems in five Mill Valley California locations We believe that the purchase and installation of LRAD goes a long way to improve the resiliency and redundancy of our communication systems Mill Valley Fire Chief Tom Welch said LRAD systems are highly effective in communicating warnings instructions and notifications throughout incident sites and over vast areas during life threatening events 97 The City of Newport Beach plans to spend 200 000 to replace three rusty tsunami warning sirens on the Balboa Peninsula with LRAD siren public address systems The LRAD systems are expected to be installed by the end of 2019 98 In October 2020 Laguna Beach California tested its expanded outdoor warning system of 13 Long Range Acoustic Devices mounted on buildings throughout the city The solar powered devices broadcast recorded evacuation messages in case cell service is disabled during a disaster 99 Seven new LRAD emergency siren systems are scheduled for installation in southern Marin County in 2022 100 The Berkeley California city council approved the installation of a Genasys outdoor warning system to alert residents of fires earthquakes tsunamis and other disasters The system is capable of running on solar powered battery backup and being controlled remotely via satellite 101 Public safety officials in Berkeley California unveiled the city s new Genasys emergency warning network during the September 17 2023 Fire Ready Fest Ten systems that broadcast both sirens and voice messages have been installed on buildings throughout Berkeley to provide another layer of reaching residents and visitors in the event of serious emergencies Five more systems are projected to be installed by early 2024 102 High seas anti piracy edit nbsp LRAD on RMS Queen Mary 2On November 5 2005 the luxury cruise ship Seabourn Spirit employed an LRAD to repel pirates who attacked the vessel with rocket propelled grenades about 115 km off the coast of Somalia 103 The effectiveness of this device during the attack is not completely clear but the pirates did not succeed in boarding the vessel and eventually fled The Liberian flagged vessel MV Biscaglia was attacked on November 28 2008 The security detachment aboard Biscaglia was reported to have used an LRAD device in an effort to repel attackers armed with assault rifles and rocket propelled grenades Following a one sided shootout the ship was seized and the unarmed security contractors abandoned ship leaving the ship and crew to the pirates 104 The incident caused the usefulness of LRADs to be called into question by Lloyd s List 105 The security detachment s reported use of LRAD is not completely clear as The Wall Street Journal makes no mention of LRAD being used during the incident 106 In January 2011 the Spirit of Adventure a cruise ship sailing through the Indian Ocean deployed an LRAD system as part of its defensive measures when being pursued by pirates 107 S Y Hideaway used an LRAD in 2016 to deter suspected pirates in the Gulf of Aden 108 Major users edit nbsp Algeria Used for the first time in April 2019 during the pacific walk against Bouteflika on the Algerian population nbsp Australia Victoria Police the Western Australian Police the South Australia Police the Queensland Police Service and the Australian Federal Police have confirmed they have purchased the devices 109 nbsp Azerbaijan Azerbaijan police 110 nbsp Brazil nbsp Canada Multiple police departments 111 nbsp Czech Republic Used first time on March 18 2017 by the Police of the Czech Republic 112 nbsp Georgia nbsp Greece nbsp Honduras nbsp Hong Kong Police Tactical Unit and Police Negotiation Cadre PNC of the Hong Kong Police Force nbsp India Delhi Police nbsp Israel Ministry of Defense Israel Police nbsp Japan nbsp New Zealand New Zealand Police 113 114 nbsp Norway Norwegian Navy onboard Fridtjof Nansen class frigates nbsp Philippines Philippine National Police 115 Philippine Coast Guard 116 nbsp Poland Polish Police Polish Police have it but for legal reasons it s not used nbsp Romania Used first time on June 7 2015 by Jandarmeria Romana nbsp Singapore Used by the Singapore Armed Forces nbsp South Africa Used by the South African Police Service 117 nbsp Spain Reported use by Catalan Police 118 nbsp Sweden Swedish Navy 119 nbsp Thailand nbsp Turkey Used by the Turkish Naval Forces nbsp United Kingdom Ministry of Defence nbsp United States Multiple police departments US Navy US Coast Guard and US Army nbsp Vietnam Being used on board DN 2000 class ships of the Vietnam Coast Guard s fleet See also editAcoustics HyperSpike MegaphoneReferences edit CITY OF PITTSBURGH SETTLES G 20 LAWSUITS ACLU Pennsylvania November 14 2012 Retrieved May 11 2022 a b c d e f g h i English Lawrence February 21 2022 What s an LRAD Explaining the sonic weapons police use for crowd control and communication The Conversation Retrieved February 22 2022 USS Cole DDG 67 Determined Warrior Naval History amp Heritage Command Archived from the original on May 31 2019 a b c d e LRAD The Sound of Possible Excessive Force Richmond Journal of Law and Technology November 30 2019 Retrieved February 23 2022 a b c d e LRAD overview and product guide PDF Genasys a b Maritime Community amp Safety Genasys Inc October 7 2020 Retrieved February 23 2022 Speech Intelligibility Papers Section 4 Archived from the original on January 23 2011 Retrieved December 21 2010 Beranek Leo L 1986 Acoustics p 132 American Institute of Physics a b Blackstock David T 2000 Fundamentals of Physical Acoustics p 456 John Wiley and Sons LRAD Solutions Genasys Inc Retrieved February 23 2022 a b The Critical Communications Company Genasys APAC Retrieved February 23 2022 a b Sindelar Daisy March 13 2013 Explainer LRAD What Is It And How Does It Work RadioFreeEurope RadioLiberty Retrieved February 23 2022 Tan Yvette October 29 2021 Lasers and giant speakers How airports chase birds off the runway Mashable Retrieved February 23 2022 Wickman Allie August 23 2011 LRAD Corporation Receives LRAD RX Systems Order to Remotely Secure Oil Platforms Benzinga Retrieved February 23 2022 Oil amp Gas Platforms Genasys Inc Retrieved February 23 2022 1910 95 Occupational noise exposure Occupational Safety and Health Administration a b Bondy Halley September 30 2019 How the LRAD Went From a Pirate Deterrent to a Police Crowd Control Tool The Daily Beast Retrieved June 7 2020 a b Kesslen Ben May 22 2019 Plug your ears and run NBC News Retrieved June 7 2020 Long Range Acoustic Device Industry Applications Public Safety amp Security Solution Lradx com Retrieved June 26 2019 Crowd Control with Long Range Acoustic Devices Can Cause Permanent Hearing Loss Academy of Doctors of Audiology Retrieved September 13 2021 Acoustic Weapons Fact Sheet ACLU July 14 2016 a b c Chang Charis December 21 2016 Why is it OK to use this against our own citizens news com au Retrieved February 22 2022 a b Australian police authorities buying up sound weapons ABC Radio National May 17 2016 Retrieved February 22 2022 a b McCutchan Ellen February 17 2022 Sonic weapons were used by police in Canberra s protests but only to broadcast messages rather than do harm ABC News RMIT ABC Fact Check Australian Broadcasting Corporation Retrieved February 22 2022 Archived copy Archived from the original on June 29 2015 Retrieved June 27 2015 a href Template Cite web html title Template Cite web cite web a CS1 maint archived copy as title link Do Brna se kvuli demonstracim sjeli policiste ze Specialnich poradkovych jednotek z cele republiky Policejnidenik cz in Czech June 26 2015 Tydenik Policie November 18 2020 V centru Prahy probehlo k vyroci 17 listopadu nekolik shromazdeni i pochodu Nejproblematictejsi byl ten proti vladnim opatrenim tydenikpolicie cz Tydenik Policie November 17 2021 Thousands of opponents of government measures and vaccinations demonstrated in the Old Town Square in Prague tydenikpolicie cz Tydenik Policie November 26 2021 During the march in Prague the police had to repeatedly crack down on Feyenoord fans tydenikpolicie cz Tydenik Policie January 1 2022 Police detained 10 people during New Year s Eve celebrations in the center of Prague One person had to be detained for violence against an official tydenikpolicie cz Tydenik Policie March 13 2023 The result of the incident in front of the National Museum in Prague Twenty people in handcuffs three injured police officers tydenikpolicie cz FM Mediaservice November 6 2020 LRAD 100X flexibel kraftvoll und hochste Verstandlichkeit feuerwehrmagazin de Epidei3h systhmatos LRAD gia antimetwpish oxlwn se Enoples Dynameis kai Swmata Asfaleias Doyreios Ippos March 13 2020 Retrieved September 27 2020 Hxhtika yperopla sthnontai sta synora toy Ebroy apo thn ELAS se synergasia me ton Strato Kai 4 nea Drone Nea Eidhseis Ekdhlwseis sthn 3an8h in Greek September 26 2020 Retrieved September 27 2020 Japan coastguard expels North Korean fishing flotilla Ftchinese com Darby Andrew February 6 2009 Whalers attack activists at sea The Age Melbourne Sea Shepherd Conservation Society USA Video Operation Waltzing Matilda Operation Waltzing Matilda Sea Shepherd Conservation Society Archived from the original on January 3 2010 Sea Shepherd Battles Japanese Whalers in the Ross Sea Sundance Channel 7 February 2009 Street Fight on the High Seas The New Yorker January 12 2010 Retrieved January 16 2010 Ride Of The Valkyries Japanese Whalers Claim Sea Shepherd Harasses The Nisshin Maru With Classical Music Underwatertimes com Tokyo February 9 2010 Retrieved January 1 2011 New Zealand Herald June 29 2022 Revealed Police used sound cannons against Parliament protesters nzherald co nz Otago Daily Times June 29 2022 Sound cannons deployed for first time odt co nz Potezna bron sluzy jako zwykly glosnik Policyjny system LRAD pod lupa prokuratury Rmf24 pl in Polish January 9 2013 krakow wyborcz March 25 2020 Radiowoz z naglosnieniem jezdzi po Krakowie Emituje apel o pozostanie w domach krakow wyborcza pl Mak Zrodlo March 22 2020 Radiowozy z glosnikami na ulicach tvn24 pl Sharon Salim August 5 2022 She s preventing wildlife from hitting planes at Changi Airport There are surprises every day ChannelNewsAsia com TeleMadrid March 19 2020 La Policia de Leganes lanza mensajes de voz a sus vecinos con un super altavoz telemadrid es Sonic weapon deployed in London during Olympics BBC News May 12 2012 Retrieved May 11 2012 ABC News Technology amp Science August 25 2004 Amanda Onion RNC to Feature Unusual Forms of Sound Unusual Forms of Sound to Emanate From RNC Urbina Ian September 24 2009 Protesters Are Met by Tear Gas at G 20 Conference The New York Times Retrieved June 26 2019 thetwos YouTube Martin Adam October 25 2011 Occupy Oakland s Tent City Is Gone The Atlantic Wire Retrieved October 26 2011 Occupy Wall Street Police use military megaphone to amplify their point to protesters New York Daily News New York November 18 2011 Retrieved February 15 2015 Whalen Matthew Vernon A People s Librarian Part Two with Aeliana Boyer The Hard Times Review Hard Times Review Retrieved April 15 2022 As it Happens NATO in Chicago NBC Chicago June 15 2012 Bill Mich October 8 2013 Salisbury Police Utilizing New LRAD System Wboc com DAY FIVE WRAPUP McCulloch blasts Nixon for replacing St Louis County Police control St Louis Post Dispatch August 14 2014 Video NYPD Uses Military Grade Sonic Weapon on Eric Garner Protesters Alternet org Tom O Dare March 19 2015 Myrtle Beach police going high tech for Bikefest Myhorrynews com NYPD LRAD warning message for protesters 4 29 15 YouTube April 29 2015 Archived from the original on December 21 2021 Justin Davis Police Deploy Tear Gas on Crowds Outside of Hot 97 s Summer Jam Complex Complex com Benjamin F Powell November 5 2015 GDP New Long Range Audio Technology Could Save Lives Wfmynews2 com Police order anti Trump protesters to disperse Breitbart News May 28 2016 Archived from the original on December 21 2021 via YouTube Enzinna Wes October 31 2016 I Witnessed Cops Using Tear Gas Rubber Bullets and Sound Cannons Against Anti Pipeline Protesters Motherjones Ted Hart November 21 2016 CPD demonstrates new crowd control device Nbc4i com Records show D C Police used an LRAD sound cannon to direct crowd flow during the Women s March Muckrock com November 20 2017 Henry Culvyhouse February 17 2017 UMES concert canceled due to unruly crowd Delmarvanow com Ashley Tressel April 18 2017 New loudspeaker ensures MCSO will be heard loud and clear Ukiah Daily Journal Phoenix police pick up approval 95K for long range crowd control speakers Ktar com November 10 201 WROC Staff August 19 2019 Dozens arrested after Puerto Rican Festival RochesterFirst com Protest in Phoenix over death of George Floyd ends in arrests property damage YourValley net May 29 2020 Video of protest with LRAD use Twitter com Retrieved June 4 2020 Portland Mayor Ted Wheeler holding news conference about continued protests Watch live June 5 2020 Police Use Acoustic Device On Crowd 1190 KEX Radio iHeart Media Retrieved June 6 2020 What is LRAD PPB explain their sonic tone device KOIN com June 6 2020 https www seattle gov documents Departments OPA ManagementAction 2020OPA 0741 2021COMP 0032 MAR 06 09 21 pdf bare URL PDF MYERBERG ANDREW May 31 2021 Closed Case Summary Allegations of Misconduct amp Director s Findings PDF Report Seattle Office of Police Accountability 2020OPA 0741 Elijah Koerri August 24 2020 Livestream of 24 August 2020 Jacob Blake Protests Facebook Timestamp 2 06 56 Retrieved August 25 2020 Scenes from Kenosha after shooting of Jacob Blake Facebook August 24 2020 Timestamp 0 37 55 Retrieved August 25 2020 Kenosha Courthouse Protest Twitter com Retrieved August 26 2020 Police use sound cannon at Rochester protest RPD says officers were hit with bottles eggs DemocratandChronicle com Protesters arrested outside Rochester City Hall as police break up occupation DemocratandChronicle com US military police sought use of heat ray to disperse White House protesters The Guardian September 17 2020 Savannah Behrmann September 17 2020 National Guard major Military police asked about using heat ray against DC protesters usatoday com Protesters Were Supposed To Hear Warnings Before Federal Police Moved In They Didn t NPR Julia Tullos September 22 2020 Cuyahoga County Sheriff makes changes after May 30 riot in Downtown Cleveland Cleveland19 com Jonathan Choe November 5 2020 Use of LRAD speaker by Seattle police for crowd control spurs questions concern komonews com University Hill Disturbance Update Boulder Police Department Long Range Acoustic Device LRAD deployed in front of BLM crowd at Brooklyn Center MN mehabe com April 13 2021 Wakefield police used sonic blast a high pitch alarm to incapacitate Rise of the Moors suspects masslive July 13 2021 Retrieved July 13 2021 Oklahoma neighborhood left dazed after early morning drug raid ends in multiple arrests kfor November 23 2021 Retrieved July 13 2021 CMPD Negotiators Helped Individual Who Climbed Electrical Tower charlottenc gov January 9 2022 Retrieved January 9 2022 Susan C Schena April 20 2018 Siren vs Voice Mass Evacuation Systems Tested Menlo Park Atherton CA Patch CONTRIBUTED CONTENT April 18 2019 Menlo Park Fire demonstrates early warning system for earthquakes and other natural disasters inmenlo com Tsunami Awareness Week 2018 lagunabeachcity net Cornell Barnard June 27 2019 It s loud Mill Valley installs new emergency warning system abc7news com Kristina Houck June 27 2019 Mill Valley To Test New Emergency Sirens patch com Hillary Davis August 20 2019 Newport Beach to replace rusty tsunami warning sirens Los Angeles Times Daniel Langhorne October 30 2020 Laguna Beach s wildfire mitigation plan still a work in progress lagunabeachindy com Giuseppe Ricapito January 22 2022 Southern Marin disaster sirens to be replaced marinij com Iris Kwok June 27 2022 Here s where Berkeley s first 5 speaking emergency sirens will be installed berkeleyside org City of Berkeley August 31 2023 New siren will signal an emergency need to seek information berkeleyca gov Christine Smith September 17 2023 Berkeley tests out new emergency sirens nbcbayarea com John Ramos September 17 2023 Berkeley unveils siren system at Fire Ready Festival cbsnews com sanfrancisco I beat pirates with a hose and sonic cannon BBC News May 17 2007 Login Timesonline co uk David Osler 2 December 2008 Sonic solution may not be a sound investment Lloyd s List London Informa Retrieved 13 April 2011 Geeta Anand and John W Miller January 31 2009 Hijacked on the High Seas wsj com Sloan Gene January 17 2011 Cruise ship blasted pirates with sonic wave USA Today Retrieved July 17 2011 William Bruton February 2017 Standoff Dockwalk com Australian police authorities buying up sound weapons The Law Report ABC Radio May 17 2016 This Pain Inducing Acoustic Device Used to Control Crowds in Azerbaijan Might Be U S Made The Atlantic March 14 2013 Sioui Marie Michele May 22 2014 La police de Montreal se dote de canons a son La Presse Premiera akusticke zbrane v Opave Sef policie Odvedli jsme excelentni praci Denik cz in Czech March 19 2017 Revealed Police used sound cannons against Parliament protesters NZ Herald Retrieved June 29 2022 Francis Oscar June 29 2022 Sound cannons deployed for first time at protest Otago Daily Times Online News Retrieved June 29 2022 Calayag Third Anne Peralta Malonzo and Keith November 14 2017 Riot police level up defense with sonic weapon Sunstar Retrieved June 26 2019 MaxDefense Philippines Facebook com Archived from the original on February 26 2022 Retrieved June 26 2019 CSIR confirms legality of using LRAD units EWN September 1 2016 http www eldiario es politica Centenares personas recorren Madrid Gamonal 0 219078935 html El Diario News Los mossos utilizan un canon de sonido para dispersar a los manifestantes en Barcelona Mote med lokala fiskare Operation Atalanta blogg forsvarsmakten se Retrieved June 26 2019 External links edit nbsp Wikimedia Commons has media related to Long Range Acoustic Device Retrieved from https en wikipedia org w index php title Long range acoustic device amp oldid 1191724275, wikipedia, wiki, book, books, library,

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