Factors Affecting Traffic Noise and Annoyance from Different Types of Roads: A Case Study in Nakorn Pathom Province, Thailand

This study investigated factors associated with road traffic noise and residents’ annoyance from three distinct types of roads (major arterial, minor arterial, and collector roads). Nine sampling locations in Thailand’s Nakorn Pathom Province were chosen for the measurement of noise levels and three contributing characteristics: traffic volume, vehicle speed, and the proportion of heavy to total vehicles. Along with a housing survey, face to face interviews with a total of 387 roadside dwellers recorded their sociodemographic data, activity-based locations, and noise impacts experienced. A statistical analysis based on Spearman correlation revealed a positive relationship between traffic volume and traffic noise level on major arterial (r=0.607) and collector roads (r=0.885). Residents around collector roads were more sensitive than those along the main arterial road, in spite of having lower noise levels and less intense traffic patterns. Longer housing setbacks appeared to be a key factor in reducing noise annoyance from all road types, according to an exact logistic regression analysis (OR=0.11, 95% CI: 0.003, 0.73 for the major arterial road; OR=0.29, 95% CI: 0.10, 0.78 for the minor arterial road; and OR=0.32, 95% CI: 0.12, 0.84 for collector roads). However, performing activities in closed areas (OR=0.05, 95% CI: 0.01, 0.17 for the minor arterial road; OR=0.22, 95% CI: 0.54, 0.90 for collector roads) and living in soundproof structures (OR=0.05, 95% CI: 0.001, 0.31 for collector roads) played additional roles to reduce the annoyance of residents along the roads with shorter setback lines.