title: Critical assessment of day time traffic noise level at curbside open-air microenvironment of Kolkata City, India.
abstract: BACKGROUND
  The objective of the research work is to assess day time traffic noise level at curbside open-air microenvironment of Kolkata city, India under heterogeneous environmental conditions.
  
  
  RESULTS
  Prevailing traffic noise level in terms of A-weighted equivalent noise level (Leq) at the microenvironment was in excess of 12.6 ± 2.1 dB(A) from the day time standard of 65 dB(A) for commercial area recommended by the Central Pollution Control Board (CPCB) of India. Noise Climate and Traffic Noise Index of the microenvironment were accounted for 13 ± 1.8 dB(A) and 88.8 ± 6.1 dB(A) respectively. A correlation analysis explored that prevailing traffic noise level of the microenvironment had weak negative (-0.21; p < 0.01) and very weak positive (0.19; p < 0.01) correlation with air temperature and relative humidity. A Varimax rotated principal component analysis explored that motorized traffic volume had moderate positive loading with background noise component (L90, L95, L99) and prevailing traffic noise level had very strong positive loading with peak noise component (L1, L5, L10). Background and peak noise component cumulatively explained 80.98 % of variance in the data set.
  
  
  CONCLUSIONS
  Traffic noise level at curbside open-air microenvironment of Kolkata City was higher than the standard recommended by CPCB of India. It was highly annoying also. Air temperature and relative humidity had little influence and the peak noise component had the most significant influence on the prevailing traffic noise level at curbside open-air microenvironment. Therefore, traffic noise level at the microenvironment of the city can be reduced with careful honking and driving.
authors.affiliation: Department of Civil Engineering, Jadavpur University, Kolkata, 700032 India.
authors.forename: Anirban
authors.initials: A
authors.lastname: Kundu Chowdhury
authors.affiliation: Department of Civil Engineering, Jadavpur University, Kolkata, 700032 India.
authors.forename: Anupam
authors.initials: A
authors.lastname: Debsarkar
authors.affiliation: Department of Civil Engineering, Jadavpur University, Kolkata, 700032 India.
authors.forename: Shibnath
authors.initials: S
authors.lastname: Chakrabarty
keywords: Background noise component; Correlation analysis; Noise climate; Peak noise component; Principal component analysis; Traffic noise index; Traffic noise level