When a person is exposed to loud noise over a long period of time, symptoms of NIHL will increase gradually. Over time, the sounds a person hears may become distorted or muffled, and it may be difficult for the person to understand speech. Someone with NIHL may not even be aware of the loss, but it can be detected with a hearing test.
People of all ages, including children, teens, young adults, and older people, can develop NIHL. Approximately 15 percent of Americans between the ages of 20 and 69—or 26 million Americans—have high frequency hearing loss that may have been caused by exposure to loud sounds or noise at work or in leisure activities.
Recreational activities that can put someone at risk for NIHL include target shooting and hunting, snowmobile riding, woodworking and other hobbies, playing in a band, and attending rock concerts. Harmful noises at home may come from lawnmowers, leaf blowers, and shop tools. Occupational environments with high levels of noise are the source of occupational noise induced hearing loss*.
Information taken from www.nidcd.nih.gov