Answer / avi

NVH,is the study and modification of the noise and
vibration characteristics of vehicles, particularly cars
and trucks. While noise and vibration can be readily
measured, Harshness is a subjective quality, and is
measured either via "jury" evaluations, or with analytical
tools that provide results reflecting human subjective
impressions. These latter tools belong to the field known
as "psychoacoustics."

Answer / deepak

Noise vibration and harshness is related to machinery, sound waves for horn, music system and of course for automobile
If the 0 db then good( No NVH) silence zone
if 10-20 low
if 20-30 moderate
if 30-40 high
if 40-50 very high
above this is not safe for human being, up to 40 is limited for human being

Answer / sundhara narasimhan

0 dB is the auditory threshold at 1 kHz. Frequency between 2kHz and 4kHz is lowest frequency level that is heard by human.

Human perception level is 0 dB.
Hearing damage during long-term effect is approx. 90 dB.
Hearing damage during short-term effect is approx. 120 dB.
Threshold of pain happens at 134 dB.

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