<p>Noise-induced hearing loss often presents as a decreased sensitivity to pure tones, with the presence of an audiometric notch serving as an indicator of effects of noise on hearing. This study aimed to (a) document the occurrence of audiometric notches and (b) investigate the time of onset of these notches in relation to varying durations of occupational noise exposure. This cross-sectional study included 102 bus drivers, aged 25 to 40 years, who had been exposed to noise for 6 months to over 10 years, along with 102 age-matched controls without noise exposure. Pure tone audiometry was conducted. The presence of audiometric notches and their time of onset by exposure duration was evaluated. Fifty-five drivers exhibited audiometric notches (12 - right ear, 12 - left ear, and 31 binaural), compared to only four individuals in the control group. Audiometric notches began to appear in drivers with 2.1 to 4 years of noise exposure, though statistically significant notches were observed only in those exposed for over 10 years. ROC analysis identified 66 months as the threshold for predicting the occurrence of notches with high sensitivity and specificity. Though audiometric notches appear with just 2.1 to 4 years of exposure to noise, a significantly higher number of persons with notches are seen only in the group exposed to noise for &gt;10 years. The results suggest that a notched audiogram may not always be directly linked to noise exposure.</p>