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Measurement of Noise

dB

type of noise
0dB Threshold of Audibility - Rustle of leaves
30dB Quiet conversation or in a quiet location in the country
45dB Typical office space. Ambience in the city at night
50dB Background noise in an office
60dB The sound of an average radio
70dB The sound of a car passing on the street
80dB An intercity train from a station platform/loud music in a home
90dB Pneumatic drill at 3 metes / sound of a truck passing on the street
100dB Jet plane taking off at 50 metes /sound of a rock band
115dB Limit of sound permitted in industry / Screaming baby
120dB Deafening
140dB Threshold of pain

dB is Decibel - a unit for measuring the relative strength of a signal. Usually expressed as the logarithmic ratio of the strength of a transmitted signal to the strength of the original signal. A decibel is one tenth of a "bel".

 

 

 

2008/8/1 14:17:49