Certain sound frequencies are exclusively audible to teenagers, and some retailers utilize devices that produce these specific sounds to deter them from loitering. Typically, humans possess a broader capacity to perceive various frequencies in their youth, which gradually diminishes as they age. These high-frequency sounds are often referred to as “mosquito tones” due to their similarity to the buzzing of mosquitoes. They can be effective at preventing loitering, but their use has raised concerns about potential negative effects on young people’s hearing and general well-being.