How Loud is too loud? Experts agree that continued exposure to noise above 85 dB (decibels, the measure of sound) will, over time, cause hearing loss. To know if a sound is loud enough to damage your ears, it is important to know both the loudness level (measured in decibels, dB) and the length of exposure to the sound. In general, the louder the noise, the less time required before hearing loss occurs.

According to the National Institute for Occupational Safety and Health (NIOSH), the maximum exposure time before your hearing is endangered at 85 dB is 8 hours. Unfortunately, the decibel scale is logarithmic, which means that a mere 3 dB increase represents a doubling of sound intensity. A four-hour dose of sound at 88 dB is roughly the same as an eight-hour dose at 85 dB. At 110 dB, the recommended maximum exposure time is only about a minute and a half. If you must be exposed to sound above 85 dB for an extended period of time, it is recommended that you use some form of hearing protection (see Plugs 'n' aids).

Below is a table of various sounds we may confront in our everyday lives and the approximate decibel levels for these sounds. It's important to note that although the dB levels are typical, actual noise levels may vary depending on the specific situation. Exposure to noise levels above 85 dB for 8 hours is the Federal threshold for hearing protection. Levels above 90 dB can cause permanent hearing loss with relatively short exposure. Noise levels above 140dB can cause damage to hearing after just one exposure.

0 decibels is the reference noise (the sound of soundlessness :) The loudest possible sound is rated at 194 dB. The sounds in red can be considered hearing hazards.

Sound	Decibel Level
softest audible sound	0 dB
normal breathing	10 dB
rustling leaves	20 dB
whispering	25 dB
clothes dryer	60 dB
normal conversation	60 dB
dishwasher	65 dB
car	70 dB
busy traffic	75 dB
alarm clock	80 dB
noisy restaurant	80 dB
average factory	85 dB
screaming child	90 dB
subway train	100 dB
diesel truck	100 dB
jackhammer	100 dB
helicopter	105 dB
power mower	105 dB
shouting in ear	110 dB
live rock music	90-130 dB
football stadium	117 dB
band concert	120 dB
thunder	120 dB
car horn	120 dB
jackhammer	130 dB
air raid siren	130 dB
noisy squeeze toys	135 dB
PAIN STARTS	140 dB
gunshot	140 dB
jet engine	140 dB
rocket launching	180 dB
loudest sound	194 dB

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  Video 15: Nancy Nadler: 28 million American with hearing damage