Police planned to use 150 decibel sound cannon to control protesters at Chicago NATO summit

In preparation for May’s NATO summit in Chicago, the city’s police force ordered a sound cannon to help them deal with the expected large number of anti-war protesters.

The cannon emits high-pitched sounds up to 150 decibels that can be heard up to 1,600 feet away, that’s about a third of a mile. A 150 dB blast from the cannon is louder than standing next to an aircraft taking off or someone firing a gun right next to you. The pain-threshold in humans is about 110 – 120 decibels, so this thing is going to hurt.

Karen Piper, a former visiting professor at Carnegie Mellon University who attended the G20 summit in Pittsburgh, sued the city after allegedly sustaining permanent hearing loss when the city used their sound cannon. “The intensity of being hit at close range by a high-pitched sound blast designed to deter pirate boats and terrorists at least a quarter mile away is indescribable. The sound vibrates through you and causes pain throughout your body, not only in the ears. I thought I might die,” Piper, now an English professor at the University of Missouri, said in a press release. “It is shocking that the device is being promoted for use on American citizens and the general public.”

Whilst the police obviously need to be equipped to control rioting, the use of sonic weapons is worrying, particular as they have a range of up to 1/3 of a mile – if a cannon is used against a hostile front-line of a crowd, many more behind them are going to suffer too.

Not only is permanent hearing loss a certainty for those hit, tinnitus will be a problem too. The NATO summit has already happened and from reports it looks like even though there was trouble, the sound cannon wasn’t used.

The quote above comes from a Better Hearing Institute press release and you can read more here.