The WHO estimates 1.1 billion teens and young adults are putting their hearing at risk by exposing themselves to damaging sound levels from personal audio devices, bars, nightclubs, and other entertainment venues. Exposure to noise levels of 100 dB for longer than 15 minutes is not safe. Hair blow dryers and subway trains are associated with those levels! Even half of children's noise-restricting headphones don't limit volumes as advertised.
PositiveTip: Limit exposure by using earplugs in loud venues, turning down the volume, and taking short breaks from listening.