The Status of Noise Pollution in the Major Traffic Intersections of Khulna Metropolitan City in Bangladesh and its Possible Effect on Noise-Exposed People

This study was conducted in the Khulna metropolitan city to determine the status of noise pollution at major traffic intersections and assess the possible effect of noise on regular noise afflicted people. For this research, five busiest roadways and traffic intersections; two mixed zone and three commercial zones were selected purposively and 'ST-8850 Sound Level Meter' was used to record the noise pressure level. Average noise pressure level and some noise parameters (Leq, L10, L50, L90, and Lnp) were measured at different shifts in each location both on working days and holidays. The result evidently specified that noise level in all major traffic circles of Khulna metropolitan city was much higher than the recommended threshold of acceptable noise level set by the Department of Environment (DOE) of Bangladesh. It was observed that the mixed area (Sonadanga, Gollamari) tends to have a higher average noise level than those of the commercial area (Shibbari, Notunrasta, Dakbangla). The noise pollution level (Lnp) in mixed areas varied from 92.77 dB (A) to 104.74 dB(A) on working days and 86.9 dB(A) to 105.5 dB(A) on holidays. On working days, the highest Leq was observed 92.65 ± 4.15 dB(A) in Sonadanga (mixed area), whereas the lowest was 85.13 ± 2.83 dB(A) in Dakbangla (commercial area). However, on holidays the highest level of Leq was found 90.41 ± 2.25 dB(A) in Sonadanga, while the lowest levels were 80.43 ± 3.20 dB(A) in Dakbangla. One-way ANOVA with LSD post-hoc test results illustrated that on working days there was a significant difference between the noise pollution levels (NPL) in different shifts of day time (F = 8.412, p