Analysis of Occupational Noise-Induced Hearing Loss Among Coal Mine Workers in Enugu State, South East Nigeria

Noise-induced hearing loss (NIHL) is a prevalent but largely underreported occupational hazard in Nigeria's coal mining sector. This study analyses the extent of occupational NIHL among coal mine workers at the Enugu Coal Corporation and surrounding small-scale mining operations in Enugu State, South East Nigeria. A cross-sectional occupational health survey was conducted involving 200 mine workers, with noise exposure assessments using Type 1 sound level meters and pure-tone audiometric tests administered by a certified audiologist. Workers' occupational histories, hearing protection usage, and noise exposure duration were documented through structured questionnaires. Findings reveal that 68 percent of workers tested exhibited audiometric evidence of high-frequency hearing loss, with the greatest deficits recorded in the 4,000 hertz range consistent with NIHL patterns. Underground haulage operators and blasting crew members recorded the highest mean noise exposure levels, averaging 98 decibels, well above the 85-decibel action limit. Personal protective equipment compliance was below 30 percent among the sampled workforce. The study recommends mandatory audiometric surveillance, engineering noise controls on equipment, and structured hearing conservation programmes. These findings contribute to occupational health literature on the mining sector in South East Nigeria and establish the need for stronger enforcement of the Factories Act and Mines Regulations. Keywords: noise-induced hearing loss, coal mining, Enugu State, occupational health, audiometry.