3. ACOUSTIC DEVICES Description: Acoustic devices, also called “sound cannons”, “loud hailers” and “hail and warn devices”, are loudspeaker devices that can project high-volume sound over long distances. While they can be used to convey information like normal public address systems, they can also produce high-volume sounds at various frequencies, including at levels and frequencies that can be highly irritating or cause pain. Acoustic devices can be free-standing, vehicle-mounted, embedded in riot control shields, handheld or body-worn (i.e., over the shoulder or strapped to the chest). Intended purpose: The most commonly used acoustic devices can be used either to aid in voice communications, such as to give instructions or commands, or to emit a “deterrent tone” or “alert function”, such as to disperse a crowd or gain the attention of a group of people for an announcement. The alert function is designed to emit a high decibel, narrow frequency, focused set of sound waves. The narrow beam is intended to enable targeting of the sound wave to a limited area,10 with the degree of pain or irritation caused depending on the volume of and distance from the device. Possible health and/or human rights implications of use in policing assemblies: The use of acoustic devices at close range, high volume and/or prolonged periods, can lead to temporary pain, loss of balance, significant harm to the eardrums and inner ear11 and, ultimately, permanent hearing loss.12 They are relatively 10 11 12 See: Physicians for Human Rights and the International Network of Civil Liberties Organizations (­INCLO), Lethal in Disguise: The Health Consequences of Crowd-Control Weapons, 2016, p. 72, <https://w w w.inclo.net/pdf/lethal-in-disguise.pdf>. See: Amnesty International USA, On the Streets of America: Human Rights Abuses in Ferguson, (New York: Amnesty International USA, 2014) p. 14, <https://www.amnestyusa.org/reports/on-the-streetsof-america-human-rights-abuses-in-ferguson/>; and Ibid., p. 76. NATO, “Non-Lethal Weapons and Future Peace Enforcement Operations”, (2004) RTO TECHNICAL REPORT TR-SAS-040, pp. 3-11, <http://w w w.dtic.mil/cgi-bin/GetTRDoc?AD=ADA431128>.