Factors that may damage or lead to loss of the hairs and nerve cells in your inner ear include:

  • Aging. Exposure to sounds over the years can damage the cells of your inner ear.
  • Heredity. Your genetic makeup may make you more susceptible to ear damage.
  • Occupational noises. Jobs where loud noise is a regular part of the working environment, such as farming, construction or factory work, can lead to damage inside your ear.
  • Recreational noises. Exposure to explosive noises, such as from firearms and fireworks, can cause immediate, permanent hearing loss. Other recreational activities with dangerously high noise levels include snowmobiling, motorcycling or listening to loud music. Personal music players, such as MP3 players, can cause lasting hearing loss if you turn the volume up high enough to mask the sound of other loud noises, such as those from a lawn mower.
  • Some medications. Drugs, such as the antibiotic gentamicin and certain chemotherapy drugs, can damage the inner ear. Temporary effects on your hearing — ringing in the ear (tinnitus) or hearing loss — can occur if you take very high doses of aspirin, other pain relievers, antimalarial drugs or loop diuretics.
  • Some illnesses. Diseases or illnesses that result in high fever, such as meningitis, may damage the cochlea.

Comparing loudness of common sounds

What kind of decibel levels are you exposed to during a typical day? To give you an idea, compare noises around you to these specific sounds and their corresponding decibel levels:

Decibels Noise source
Safe range
30 Whisper
60 Normal conversation
70 Washing machine
Risk range
85 to 90 Heavy city traffic, power lawn mower, hair dryer
95 Motorcycle
100 Snowmobile, hand drill
110 Chain saw, rock concert
Injury range
120 Ambulance siren
140 (pain threshold) Jet engine at takeoff
165 12-guage shotgun blast
180 Rocket launch

Adapted from National Institute on Deafness and Other Communication Disorders, 2008; the National Institute for Occupational Safety and Health, 2009; and American Tinnitus Association, 2009

Maximum sound-exposure durations

Below are the maximum noise levels on the job to which you may be exposed without hearing protection, and for how long.

Maximum job-noise exposure allowed by law
Sound level, decibels Duration, daily
90 8 hours
92 6 hours
95 4 hours
97 3 hours
100 2 hours
102 1.5 hours
105 1 hour
110 30 minutes
115 15 minutes or less

Source: Department of Labor's Occupational Safety & Health Administration, 2005

Aug. 23, 2011