Tired of teens? Use the Mosquito repellent

As the 41-year-old security device inventor contemplated the problem, he recalled from his teenhood the awful buzz of an ultrasound welding machine at his father’s glue-plastics factory. He remembered that his complaints about the noise would be met with a quizzical look from workers: “What noise?”

From that impulse to help rid his local market of loiterers came his invention, “the Mosquito,” an electronic contraption that emits a high-pitched pulsating sound that can mostly be heard only by teens and people in their early to mid-20s. It works because an age-related hearing loss called presbycusis reduces the ability to hear high-pitched sounds after the late 20s. The device is mostly inaudible to older adults, young children and pets.

In the United Kingdom, the Mosquito has become the next big thing in crowd and crime control—and it may one day be coming to a teen hangout near you. The device seems to have ratcheted up the aural warfare that began a few years ago when train stations and merchants in England and elsewhere tried piping in classical music to repel young loiterers.

The Mosquito emits a sound that can be heard up to 60 ft away for 20 minutes at a time. It can be heard through earphones and over loud music. It is for commercial and official use only, and is never supposed to be used in a residential area or near a bus stop, the manufacturer says.

Young people, meanwhile, have turned the table on the technology. Many have downloaded the sound onto their cell phones, creating a ring tone that they can hear but older adults can’t. Teen Buzz, a short Mosquito ring tone, has become among the most downloaded ring tones worldwide. Some use it to alert high school classmates of recently sent text messages. For others, it’s come in handy when parents curtail use of their cell phones.

Already, the device has helped with youth crowd control at a school system in South Carolina, US. Rick McGee, emergency services manager at Richland School District Two, said that the schools purchased two Mosquitos from RMS Technologies two months ago, installing one in a vehicle and mounting the other in a commons area. “What we like about them is that you can move crowds without getting into a confrontation,” McGee said. “We use the car device at sporting events, in the parking lot after the games where people start congregating and the problems start. We’ll switch it on and immediately you’ll see heads turn around. They become irritated from the noise, and within about five minutes, they’ve all gone somewhere else.”

At his home in Merthyr Tydfil in Wales, Stapleton tried re-creating the sound from his youth. He tested various attempts on his children, until they responded at a tone of 17 kHz tone at 85 decibels. He then ramped up the irritating sound by making it peal at four times a second. Stapleton ultimately manufactured the Mosquito for commercial and law-enforcement use worldwide under his company, Compound Security Systems.

Stapleton says that at 85 decibels, the sound is equivalent to heavy traffic and would only do permanent ear damage if someone were exposed to it for eight continuous hours.
-Joe Burris (LAT-WP)