There is no question that if used to its full potential, the LRAD can cause significant damage to auditory nerves. These speculative injuries are in no way consistent with how the device operates, or how it is reported to have been used.
DOES THE SOUND OF A GUNSHOT ECHO SERIES
It’s unclear exactly how loud the messages were, but there’s no evidence the devices were used in “siren mode”.Īfter its use, there were a series of posts and reports on various outlets regarding purported injuries from the use of the device. In this case, it was used as a “loud hailer” for voice messages to be passed to those assembled for the vaccine mandate protests. Most recently, in response to the protesters gathered in Canberra and assembled on Parliament House’s lawn earlier this month, the LRAD was again deployed. In June 2020, during the Black Lives Matters protests in New South Wales, police deployed the LRAD, in a move that significantly shifted the way the technology could be used in Australia. In 2020, however, this pattern of usage began to shift.
Most use by police forces in Australia has been limited to disaster communication and for communication during events such as hostage situations. Until very recently, the use of the LRAD in public settings in Australia has been largely nonexistent. This resulted in a successful lawsuit against the City of Pittsburgh that was significant and historic as it recognised that sound can be weaponised, and cause lasting bodily harm. Voices, hearts and hands – how the powerful sounds of protest have changed over time
In September 2009 a US woman named Karen Piper suffered permanent hearing damage when she was accidentally caught within an extended period of loud emissions from an LRAD operator. What makes the power of the LRAD significant is its capacity to cause long-term physiological damage to the body. This design simultaneously ensures maximum discomfort for the target subject and maximum efficiency of the device itself. It is specially designed to be weighted to transmit sound loaded in the frequency range where human hearing is most sensitive, roughly 2,000–4,000 Hertz. The LRAD’s siren is one of its main deterrents. Since that time, the technology has proliferated, aided by a dedicated effort from its creators to make the item a staple device for communication and increasingly for crowd control in military and civil settings. This incident resulted in numerous changes in naval policy, and it also led to the creation of the LRAD. By the time they were confident their messages could be heard, it was too late. The origin of the LRAD can be traced to an event in October 2000, when the USS Cole, an American guided missile destroyer, was bombed by a small boat loaded with explosives in a terrorist attack.Īs the small vessel approached, naval personnel on board the USS Cole Anything over 140dB will cause pain for most people, but even sounds over 120dB can cause permanent hearing damage from even short periods of exposure. A 20dB increase would be a 100-fold increase in SPL.Īs a rough reference, standing directly behind a jet engine as it takes off is between 130-140dB, and a nearby gunshot rates at approximately 150db. To understand how loud 160dB is, it’s important to understand that volume, or “sound pressure level” (SPL), is not a linear measure: an increase of 10dB actually corresponds to a tenfold increase in SPL.
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