Exposure and inequity: assessing commuter vulnerability and the quality of noise environment on urban arterials

It is a well-established fact that a mobility corridor is a source of various street level noises impacting unprotected commuters. Although this fact is understood rarely has it been investigated to evince the category of commuters it affects or its intensity? The purpose of this study is to characterize and establish the noise environment, elicit the degree of noise exposure and establish the inequity that gets distributed in a common public space on vulnerable commuter categories. For this study noise levels were recorded at intersections and mid segments of corridors at 24 locations to assess the noise environments. The degree of exposure and equity were derived using a Semantic differential (SD) rating scale. The study consisted of two parts: noise survey and the traffic stream and modal attribute study. The results were analysed statistically and a rating scale developed to inform analysis and interpretation. The paper dwells on two related aspects of vulnerability; exposure and equity. The study reveals that at all locations surveyed noise levels remained far above prescribed limits. This study indicates the dominance of MT’s in terms of volume and road usage and showed that although slow commuters and NMT’s generated lesser noise on road environments inequity is foisted on them when compared to MT modes. Results indicate that the percentage of the total volume of non-motorized (NMT) commuters in the two road environments studied does not affect the noise climate. All noise descriptors indicate high noise emissions the sources of which are motorized transport as compared to the NMT’s which are susceptible and are comparatively more sensitive to this externality. The vulnerability score is derived on a rating scale. The vulnerability matrix and scores developed show high scores for slower modes indicative of the intensity of exposure based on factors evolved from the study.