#lrad

[theknightlywolfe]

Reminder:

Police are using sonic weapons against protesters that can cause permanent hearing loss

LRADs, a sound-producing device used to control crowds, can inflict permanent damage on subjects

[dzinchuriki]

on march 15, the largest protest in serbia’s history took place in the capital, with some estimates ranging between 800,000 and 1,000,000 people on the streets. however, there were incidents of organized attacks on demonstrators—people were trampled, hit with stones and firecrackers, and tear gas was deployed. the most extreme action by the police was the use of a sound cannon (LRAD), banned by law in serbia, which then triggered a stampede. dozens of people were injured.

the wave of mass protests in serbia started in november last year after the novi sad train station canopy collapse

[dontmean2bepoliticalbut]

[adafruit]

What Is an LRAD, and Why People Are Asking Us About It … 🔊 👂 http://adafruit.com/LRAD

[staysafestayvigilant]

How to protect yourself from LRAD

[ragemovement]

[kaldurcalms]

Sound warning!

If you're using earbuds, maybe don't use them to watch this. It does have built in captions.

I found the video here, but the original source is Tech Ingredients on YouTube.

The YouTube video is longer, but you need to use the in-app captions.

[theanishimori]

LRAD safety fact sheet for protesters. Get off axis first, get far away second. Folks out in the streets, this is a short guide below to staying safe from LRAD’s (long range acoustic devices). which is a form of sonic weaponry that police have deployed in recent protests to disperse crowds. I am sharing what I know not to cause alarm, but so that people are aware of what RADs are and can act to protect themselves, should they be deployed at any point. I am writing this as an electrical engineer working in audio and do not claim to be an expert on LADs or sonic weaponry. This fact sheet has been cobbled together from available information online (LAD instruction manuals, marketing datasheets, interviews, other disparate online sources) and from professional experience working in audio. LADs (Long Range Acoustical Device) have been deployed at actions in many major US cities. They produce high-frequency, highly directional sound to disperse crowds. Typical LRAD maximum SPLs (Sound Pressure Level) are 140dB-160dB. This is enough to burst eardrums even at a distance. The longer you are subjected to the sound, the more severe the damage to your hearing may be. Depending on proximity, permanent hearing damage is very possible. The best safety measure is getting as off-axis and as far away as possible before it's activated. If you can't do that: First priority is still to get as off-axis (i.e., out of its "spotlight") as you can, as far away as possible, as quickly as possible. Side-step the beam first, move away from it second. Try not to panic and abandon caution when trying to do this.” Bring earplugs, but they will not sufficiently protect you from damage alone. If you can’t get far away, treat the sound beam as a spotlight & get behind a solid object. Get behind cars, walls, etc. Many LRADs can be pivoted. Stay perpendicular to the device where possible.