Effect of Factory Process and Location on Residential Area Noise Level

Abstract

Tranquility is one of the healthy environment factors on the residential areas which elevate the standard of living of the people and their psychological well-being. On the contrary, when there is a high level of noise intrusion at home, it might deprive one of these benefits. This study measured the industrial noise intrusion level in the residential area with respect to distance. A total of 40 residences, with 8 each around 5 food and drug processing factory sites in three local government areas (Idemili North, Onitsha North, and South) of Anambra state, Nigeria were selected as study site locations. Benetech Model GM 1352 digital sound level meter was used for the measurement of environmental outdoor noise levels at a height of 1.5 m and 3 m from any reflecting surfaces. The distance between the factory sites and the residences assessed was calculated using the coordinates of the study site points obtained with A Garmin GPS 72H on the CDXzipdistance2WP function on Microsoft Office Excel. All measurements were carried out during the daytime between 6:00 am – 10:00 pm. Three categories of environmental outdoor samples of noise levels were obtained; off work-hour, and work hour which comprises of generator usage and the national grid connection hours. The computed LAeq noise intensity level obtained at the residences assessed showed that 12(30.0) and 28(70.0) of the residences assessed were quiet and moderately loud during national grid connection hours which was; quiet 32(80) and moderately loud 8(20) during off work-hours. It, however, translated to moderately loud 24(60.0) and very loud 16(40.0) during the engagement of the services of electricity generator. The Pearson correlation analysis showed that there was a strong negative correlation between the distances of the residences assessed from the factory sites and the noise level which were significant at p < 0.01 for values of r = -0.976 during generator use and 0.981 when compared with the national grid. This implies that the closer factory sites are on the residential area the higher the noise intrusion level which is not healthy.