Investigation on the hearing loss of workers exposed to noise in a ceramic plant

Objective To study the effect of noise to the hearing loss of the workers exposed to noise in a ceramic plant.Methods The hearing examination in 82 noise exposed workers (noise exposed group) in a ceramic plant and 48 non-exposed personnel (control group) were determined by model GST-68 pure tone audiometer made in Denmark.Results 18 points of noise intensities were detected and average noise intensity was( 85.7 ± 6.6 )dB(A) and 15 points (88.3％) exceeded the national occupational exposure limits.The incidence rate of hearing loss in the noise exposed group was 51.22％,significantly higher than that in control group (10.42％,P＜0.01).The duration of noise exposure ＜ 3 years,3years ～ 6 years、＞ 6 years were 16.67％,77.14％ and 81.82％ respectively.The incidence rate of hearing loss seemed to be increased gradually with duration of noise exposure increasing ( P＜0.01 ).Coneluusion The hearing loss abnormality could be caused by exposure to noise in the ceramic enterprises,precautions and measurements should be implemented. Key words: Noise; Hearing loss; Investigation; Ceramic plant