Measurement Of Noise

Health Hygiene & Sanitation

Lesson 17 : Lighting And Noise

Measurement Of Noise

Decibel is the standard for the measurement of noise.

  • The zero on a decibel scale is at the threshold of hearing, the smallest distinguishable sound.
  • on the decibel scale,
    • 20 dB is whisper
    • 40 dB the noise in a quiet office
    • 60 dB is normal conversation
    • 80 dB is the level at which sound becomes physically painful.

1
4

So How Loud Is Loud?

110dB +


Close to a train(110) >130 dB Immediate hearing damage

90 dB

Very loud

Car Horn at 5 meters(100db) >90 dB regularly can cause hearing damage.

70 - 80 dB

Loud

police whistle, city street noise

45-60 dB

Moderate

Normal conversation at close up. Normal office noise

30-40 dB

Faint

Quiet conversation, private office, recording studio.

20 dB and less

Very faint

watch ticking, whispering, sound proof room


Noice Quantum of Cities

  • Delhi- 80 dB
  • Kolkata – 87 dB
  • Bombay-85 dB
  • Chennai-89 dB etc..
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Last modified: Thursday, 26 April 2012, 12:01 PM