Assessment of Observed Building Structure Setback of Shops along an Arterial Road and Noise Intrusion Level


Roads irrespective of the type have specific standard horizontal distance measured at 90 degrees from a lot boundary to a development known as a setback. Non-observance of the recommended setbacks accommodated in any urban center’s master plan creates noise hazard to the public health and safety as the movement of vehicular traffic is not without the attendant noise. This study assessed noise intrusion level in shops along a section of Ibadan-Abeokuta road with due consideration to compliance with the recommended building structure setback. Analysis of noise descriptors evaluated in this study gave A-weighted equivalent sound pressure level average of 91.3 dBA, the daytime average sound level (LD) 92.27 dBA, traffic noise index (TNI) 41.63 dBA, the noise pollution level (LNP) 85.91 dBA and noise climate (NC) 5.38 dBA. Correlation analysis between the observed setbacks and the noise levels gave an “r” value of -.496 significant at p < .05. The paired t-test analysis showed a mean ± SD difference of 15.90 ± 7.08, and t-value of 32.99, corresponding to a two-tailed p < .05 with 215 degrees of freedom. This implies that there was a significant statistical difference between the noise levels measured at the observed and recommended setbacks