Assessment of Occupational Noise-Induced Hearing Loss Among Factory Workers in Aba, Abia State

Occupational noise-induced hearing loss (NIHL) remains a significant yet underreported public health concern in Nigerian manufacturing settings. This study assessed the prevalence and risk factors of NIHL among factory workers in Aba, Abia State, a major industrial hub in the South East geopolitical zone. A descriptive cross-sectional design was adopted, with 180 factory workers recruited through stratified random sampling across five manufacturing facilities. Data were collected using a validated structured questionnaire, audiometric tests, and sound level meter readings conducted at various workstations. Findings revealed that 61.7 percent of respondents were exposed to noise levels exceeding the 85 dB(A) permissible threshold, while 38.3 percent demonstrated measurable hearing threshold shifts. The use of personal protective equipment (PPE), specifically earplugs, was consistently low, with only 22 percent reporting regular use. Key predictors of hearing loss included duration of employment, age, and proximity to heavy machinery. The study found a significant association between years of occupational exposure and severity of audiometric impairment. Workplace health and safety regulations were poorly enforced across the sampled facilities. These findings underscore the urgent need for audiometric surveillance programs, engineering noise controls, and mandatory PPE training in Nigerian industrial workplaces. Health education campaigns targeting factory supervisors and workers are equally recommended. Policy stakeholders should prioritize routine occupational health monitoring in Abia State's growing manufacturing sector. Keywords: noise-induced hearing loss, audiometric testing, factory workers, occupational exposure, Aba.