Decibel Levels of Common Sounds

Sound intensities are typically measured in decibels (dB). A decibel is defined as 10 times the logarithm of the power ratio (power ratio is the ratio of the intensity of the sound to the intensity of an arbitrary standard point.) Normally a change of 1 dB is the smallest volume change detectable by the human ear.

Sound intensity is also defined in terms of energy (ergs) transmitted per second over a 1 square centimeter surface. This energy is proportional to the velocity of propagation of the sound.
 

Decibels 
(dB)

Degree

Sound Source

225

Deafening

12" Cannon @ 12' in front and below

195

Deafening

Saturn rocket

180

Deafening

Aircraft at take-off

160

Deafening

Ram jet

150

Deafening

Turbo jet

140

Deafening

Artillery fire

130

Deafening

Threshold of pain, decibels at or above 130 cause immediate ear damage. Hydraulic press, pneumatic rock drill

120

Deafening

Riveter, chipper, thunder, diesel engine room, fireworks display

110

Deafening

Punch press, close to a train, ball mill

100

Very Loud

Passing truck, home lawn mower, car horn @ 5 meters, wood saw, boiler factory

90

Very Loud

Decibels at or above 90 regularly cause ear damage. Noisy factory, truck without muffler

80

Loud

Noisy office, electric shaver, alarm clock, police whistle

70

Loud

Average radio, normal street noise

60

Moderate

Conversational speech

50

Moderate

Normal office noise, quiet stream

45

Moderate

To awaken a sleeping person

40

Faint

Average residence, normal private office

30

Faint

Recording studio, quiet conversation

20

Very Faint

Whisper, empty theater, ticking of watch

10

Very Faint

Threshold of good hearing

0

 

Threshold of excellent youthful hearing