Noise Induced Hearing Loss in Glass Factory Workers in Delta State Nigeria: An 8 year follow up

Background: Noise induced hearing loss is a well known recognized hazard in factory workers. This is due to the fact that the level of noise in most factories exceed the WHO acceptable limits. This was an 8 year follow up study on glass factory workers to determine the effect of noise on their hearing status over that period. Materials and Methods: Audiometry was carried out on the factory workers using a diagnostic audiometer. This was repeated after 8 years. All the workers had their ears examined prior to Audiometry which was done in a quiet area in the factory clinic. Thereafter data was collected and analysed. Results: The subsequent screening showed that all the workers had increased threshold of hearing and the Prevalence rate of hearing impairment had increased from 9.1% to 40.8%. All workers admitted to intermittent use of personal protective devices (ear muffs/ear plugs) despite being counselled on their use 8 years earlier. Conclusion: Hearing Conservation measures should be instituted in factories. Pre-employment screening should be mandatory as well as annual audiological screening and the labour laws should be strengthened to ensure adequate compliance by industries.