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Community noise levels in Ilorin metropolis were measured and analyzed. The noise climate variation was observed to be a function of time due to an increase in population density and other sources of environmental noise. There is increase in the day and night noise levels with growth in population. The noise levels have increased by 2 to 13 dB(A) in the past 20 years in Ilorin metropolis. Statistical analysis shows that the noise level exposure differs significantly from one location to another. High noise levels occur in the daytime at road junctions, followed by commercial centers and passengers loading parks. The noise map developed from this study based on the noise descriptors L D , L N , L DN , TNI, and L NP reveals high noise level exposure at the center of the city where commercial activities and clustered buildings with high population density exist. The noise map provides enough information for technical controls and interim legislation against environmental noise pollution in the metropolis.

In this paper, analysis of the energy audit of Food processing industry and Distillation and Bottling Company in Ota, Nigeria has been carried out. A walk-through energy audit of these industries was undertaken to identify the major sources of energy in use, identifying the lapses in energy usage, identifying areas to improve energy usage, determining the level of consumption of the energy sources and recommending policy measures that will enhance energy savings in the industries and Nigerian industries at large. The study observed that among a wide variation of end-use electricity consuming equipment, electric motors were the major consumer of electrical energy, accounting for 40-47% of total electric energy. Also from the identified energy use sources in the two industries, it was observed that fuel energy expended in operating the generating set, boilers or heaters in the industries had the highest value of energy use accounting for more than 65% of the total energy used. It was observed that none of the companies under review sufficiently utilized their energy as they all have their energy used ratio far below 1. This was as a result of some factors that contributed to energy waste and energy use inefficiency in the companies. Among these factors are: Poor in housekeeping of air-condition and refrigeration equipments and electric motors that dissipate much heat, use of electric motors that are weak and generate excessive noise because they have been rewound more than twice, improper lagging of boilers that lead to losing much heat, switching on of the lighting points in the day time and generation of electrical energy more than needed in the industry by some electric generator. The study concluded that energy is not sufficiently utilized in these companies and recommendations for efficient energy usage in the industries were proposed in this study.

This paper presents the results obtained from environmental noise measurement at selected locations in Ilorin metropolis. Forty-two (42) different locations throughout Ilorin were selected to establish background noise level and dominant noise sources at these selected locations. Noise level measurements and analysis for the locations were based on the noise descriptors L Aeq , L 1 , L 10 , L 50 , L 90 , and L D. The results from comparative study indicated that the equivalent noise level "L Aeq … and peak noise level "L 1 … have the highest and lowest values at road junctions/busy roads (86 dBA, 88 dBA) and low density residential areas (46 dBA, 63 dBA) respectively. The background noise level "L 90 … has the highest and lowest values at passengers loading parks "73 dBA… and low density residential areas "34 dBA… respectively. The result of this study shows that the major source of noise in Ilorin metropolis can be attributed to traffic noise. Other intrusive noise sources include noise from record player, electric generators, and hawking with loud speakers. Based on the recommendations of CEOH, WHO and HUD, only 6 locations out of 42 are under normally acceptable situation while the noise levels of other areas are not acceptable. Noting the noise emission standards, technical control measures, planning and promoting the citizens awareness about the high noise risk may help relieve noise problem in the metropolis. These data are useful as reference and guideline for future regulations on noise limit to be implemented for urban areas in Nigeria.