Tibbi-i-kar

Background: Exposure to noise can induce hearing loss. Thus noise induced hearing loss is one of the main concerns in interventional study on health effect of noise exposure. We analyzed pre and post exposure audiometeries of volunteers in a clinical trial study that we conducted for effect of noise exposure on cardiovascular system. Methods: In a clinical trial study, 100 healthy, 20-40 aged, volunteer men exposed to 90 dB noise for 30 minute. We take pre and post exposure pure tone audiometric test from all of subjects. Results: Mean of PTA among 100 subjects was reduced 0.72 dB in right ear and 0.44 dB in left ear. Mean of hearing threshold in each of 250, 500, 3000, 4000 and 8000HZ frequencies rise in left ear and was reduced in all of other frequencies in right and left ear. Conclusion: Results of our study indicated that short term exposure to 90 dB noise in interventional studies cannot produce clinically significant hearing loss.