Risk factors

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

• Aging. Degeneration of inner ear structures occurs over time.
• Loud noise. Exposure to loud sounds can damage the cells of your inner ear. Damage can occur with long-term exposure to loud noises, or from a short blast of noise, such as from a gunshot.
• Heredity. Your genetic makeup may make you more susceptible to ear damage from sound or deterioration from aging.
• 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 jet engines, can cause immediate, permanent hearing loss. Other recreational activities with dangerously high noise levels include snowmobiling, motorcycling, carpentry or listening to loud music.
• Some medications. Drugs such as the antibiotic gentamicin, sildenafil (Viagra) 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

The chart below lists common sounds and their decibel levels. The Environmental Protection Agency's (EPA) safe noise level is 70 decibels. The louder the noise, the less time it takes to cause permanent hearing damage.

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.