“The Mosquito” has been banned in several cities around the globe.

Updated 2:30 p.m.

Philadelphia teens, beware. If you’re planning to post up at a rec center after dark, your eardrums might suffer.

Since 2014, the city has been implementing a device that’s meant to shoo rowdy youths from the premises. Called the Mosquito, it emits a constant noise at such a high frequency that only young people can hear it.

Mosquitos are currently installed at 30 city-run locations around Philly, according to the Department of Parks and Recreation. From 10 p.m. to 6 a.m., they send out a high-pitched ringing sound to which anyone over age 25 is supposed to be immune — because, TL;DR, older folks’ ear hairs are dead.

What’s the point? The machines are intended to prevent loitering and vandalism by teens and young adults at public facilities. Think of them as the machine-generated equivalent of “Get off my lawn!”

Some say this age-based targeting is a form of prejudice.

“It very clearly discriminates against young people,” said Brian Conner, 20, president of the National Youth Rights Association. “It punishes non-criminal behavior, and the idea that youth are more prone to commit crimes than adults is just wrong.”

Michael Gibson is president of the Mosquito’s manufacturer, Moving Sound Technologies. He denies the discrimination charge by saying the product is intended for private property — which, he claimed, public parks basically are after they’ve closed.

“We do install in the parks in Philadelphia, but…they’re not actually activated until the park or rec center becomes private property,” Gibson told Billy Penn. “People have the right to protect their property.”

Councilmember Brian O’Neill is currently behind plans to install one at Champions Park Playground in Fox Chase. The device is included in some $300,000 in upgrades for the Northeast Philly park. His office did not return requests for comment.

The city’s Mosquito rollout began around five years ago with an installation in Chalfont Playground, also in the Northeast. At the time, Parks & Rec told the Inquirer they intended to outfit all 154 rec centers with the equipment by 2017. That hasn’t yet happened, but several dozen are out there.

Banned in several cities

Despite Philadelphia’s seemingly enthusiastic adoption, the Mosquito has been banned in several cities around the world. (FYI, here’s what the thing actually sounds like.)

Washington D.C. officials installed the anti-kid noisemakers at the Gallery Place Metro station in 2010. Youth group NYRA took issue with the effort almost immediately, and members filed a complaint alleging age discrimination. The city eventually asked the manufacturer to remove the devices.

“By calling attention to it, we were able to make it into a big deal,” NYRA’s Conner said. “We were able to make it clear that they’d be in a lot of trouble if they kept using this device.”

In 2008, the United Nations Committee on the Rights of the Child implored the United Kingdom to “reconsider…the Mosquito devices insofar as they may violate the rights of children.” Two years later, the Council of Europe’s Parliamentary Assembly agreed, stating that government agencies in their 47 member states ought to ban them.

Since then, at least four counties in England have followed suit and banned the device.

Parks & Rec defended Philly’s use of the youth-repellant machinery, saying they’re only operational at night.

“These sonic devices are just one part of a holistic safety system, and only operate when sites are closed to the public,” spokesperson Maita Soukup told Billy Penn via email. “We welcome all residents to enjoy our parks and playgrounds during the hours they are open to the public.”

Parks & Rec sites with overnight sonic devices

Cione Playground

2600 Aramingo Ave, 19125

Cohocksink Recreation Center

2901 Cedar St, 19134

Ford Recreation Center

609-39 Snyder Ave, 19148

Markward Playground

400-16 S Taney St, 19103

Kendrick Recreation Center

5822-24 Ridge Ave, 19128

Rose Playground

7401 Lansdowne Ave, 19151

East Poplar Playground

800 N 8th St, 19123

Fishtown Playground

1202-32 E Montgomery Ave, 19125

Hancock Playground

147 Master St, 19122

12th & Cambria Playground

1149 W Cambria St, 19133

American Legion Playground

6201 Torresdale Ave, 19135

Bridesburg Recreation Center

4625 Richmond St, 19137

Piccoli Playground

1501 E Bristol St, 19124

Waterloo Playground

2502-12 N Howard St, 19133

Belfield Recreation Center

2109 W Chew Ave, 19138

Water Tower Recreation Center

209-99 E Hartwell Lane, 19118

Boyle Recreation Center

13024 Stevens Road 19116

Chalfont Playground

4336 Deerpath Lane, 19154

Fitzpatrick Playground

3500 Academy Rd, 19154

Fox Chase Playground

601 Borbeck Ave, 19111

Junod Park

3102 Mechanicsville Rd, 19154

Lackman Playground

800 Bartlett St, 19115

Mitchell Playground

3694 Chesterfield Rd, 19114

Palmer Playground

11701 Thornton Rd, 19154

Picariello Playground

3325 Red Lion Rd, 19154

Lower Mayfair Playground

3001 Robbins St, 19149

Pleasant Playground

6750 Boyer St, 19119

Dorsey Playground

6501 Hegerman St, 19135

Emanuel Playground

8500 Pickering Ave, 19150

Glavin Memorial Playground

3267-81 Almond St, 19134

Barrett Playground

8th & Duncannon