Concept:Noise pollution is unwanted sound; its intensity is measured using a logarithmic scale called the decibel (dB).Explanation:Sound loudness is measured in decibels (dB).The human ear perceives sounds from 0 dB (threshold) to about 140 dB (pain threshold).A decibel is the standard unit for quantifying noise pollution levels.Other physical quantities have different SI units, but for noise, decibel is correct.