n JOURNAL OF THE NIGERIAN INSTITUTION OF MECHANICAL ENGINEERS/VOL.9 NO.2 SEPTEMBER 2019 EVALUATION AND ANALYSIS OF OCCUPATIONAL NOISE EXPOSURE IN AN AMASSED SAWMILL SITE Adinife P. Azodo 1* , Udeme V. Akpan 2 , Tochukwu C. Mezue 3 , Alexander I. Tyom 4 1, Department of Mechanical Engineering, Federal University of Agriculture, Abeokuta 2 Department of Mechanical Engineering, University of Agriculture, Makurdi, Nigeria 3 Department of Electrical and Electronic Engineering, Federal Polytechnic Oko 4 Department of Pure and Applied Physics, Federal University Wukari Abstract Modus operandi of wood processing machinery is characterized by high levels of noise which can affect the workers. This study evaluated and analyzed occupational noise exposure of sawmill operators in a sawmill session of a timber market in Ogidi, Anambra state of Nigeria on a recommended noise safety standard criterion by the Nigerian Environmental Standards and Regulation Enforcement Agency (NESREA). The range of the A-weighted equivalent sound pressure level (LAeq) obtained during the sawmill job operations was 85.8–99.7 dBA with a mean value of 95.6 dBA on idling of the machines and 99.3 – 112.3 dBA with a mean value of 107.1 dBA during the sawing operation. Analysis of the LAeq obtained on a typical noise levels scale showed 100% moderately quiet before and after the job operations and 100% very loud and uncomfortably loud on idling of the machines and sawing operations respectively during the job operation. The independent-samples t-test analyses between the observed noise level at the sawmills during the job operation and the recommended maximum permissible noise level exposure showed statistically significant difference at p< 0.05. The hazardous occupational noise level besetting the sawmill workers established in this study requires safety redress approach for safe work environment. Keywords: wood, occupational noise, sawmill, exposure, safety 1. INTRODUCTION Wood as an engineering material has found its usefulness in its raw state and processed form in many energy generation utilities and construction industries. According to Aruofor (2001), Nigeria is the largest producer of wood in Africa with an annual harvest of more than 100 million cubic meters. This may be attributed to the heavy dependency of most of the structural and construction activities in the nation on the wood resources (Aruofor, 2001). Wood by nature is adaptable for multiple numbers of domestic and industrial uses and applications (Fuwape, 2001). The maximization of wood potential and the availability to the end user in commercial quantity is only possible through mechanical processes (Babalola et al., 2018). Mechanical processing through the use of machines makes wood available in specific dimensions, sizes, and shapes (Ohagwua and Ugwuishiwu, 2011). When felled wood has been processed into beams and planks, they are called lumber or timber. The process of reducing wood logs into desired specifications, grades and marketable dimensions using sawmill machinery useful to human societies is termed sawmilling (Aina, 2006; Babalola et al., 2018), This, of course, is the major Journal of NIMechE Vol. 9 No. 2 pp 37-45 Printed in Nigeria ISSN 2141-2987 Copyright@2019, The Nigerian Institution of Mechanical Engineers (A Division of the Nigerian Society of Engineers) 37