The noise level unit 'dB(A)' uses the A-weighting because:
Choose the correct answer
It measures only traffic noise
A-weighting mimics the frequency sensitivity of the human ear, making the measurement closer to perceived loudness
It is easier to measure than linear dB
Only high frequencies are dangerous
Correct Answer
B. A-weighting mimics the frequency sensitivity of the human ear, making the measurement closer to perceived loudness
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dB(A) = A-weighted decibel level that accounts for the frequency response of the human ear. Human ear is most sensitive to 1000–4000 Hz and less sensitive at low and very high frequencies. A-weighting filter mimics this response. IS 3028 specifies noise limits in dB(A). Ambient standards: 45 dB(A) night residential, 55 dB(A) day residential.
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