NPR reports of the various parks and recreation centers in North America that are using sonic devices to repel teens from the premises. Philadelphia, for example, has 30 parks and recreation centers that are outfitted with a small speaker called the Mosquito. “It blares a constant, high-pitched ringing noise all night long — but one that only teenagers and young adults can hear,” reports NPR. “Anyone over age 25 is supposed to be immune because, basically, their ear cells have started to die off.” From the report: Philadelphia parks officials have been installing the device since 2014, reported WHYY’s Billy Penn, intending to shoo rowdy youths from the premises. And it’s not the only U.S. city to do so. Mosquito’s Vancouver-based manufacturer Moving Sound Technologies works with roughly 20 parks departments around the country to implement the youth-repellent devices, says president Michael Gibson. It’s intended to prevent loitering and vandalism by teens and young adults at public facilities. But some say this age-based targeting is a form of prejudice. Philadelphia City Council member Helen Gym refers to the devices as “sonic weapons” — and she’s working to get them removed.
[I]n Philadelphia, Parks & Recreation defends its use of the Mosquito, saying the devices are operational from 10 p.m. to 6 a.m. only, and they’re just one part of an overall anti-vandalism strategy that includes fences and gates, security cameras and night watch staff. For now, the city is moving forward with installation. Despite the backlash, two new Mosquito devices are being installed at other city playgrounds as part of major renovation projects.