Analysis of Noise Induced Hearing Loss and the Cardiovascular System Impact in Railway Workers

Objectives To understand the risk of noise induced hearing loss of workers in railway site in Beijing area, in order to provide the methods of protecting the workers' health, and guaranteed the safety of transportations and productions.

Methods The on site detection of noise intensity in the workplaces was carried out. Using the stratified cluster sampling, 360 workers exposed to noise were selected as the exposure group in the occupational health examinations. The random sample of 100 workers exposed to pure tone audiometry is set for the control group. The association of rate of hearing loss, abnormal electrocardiogram rate, and abnormal blood pressure rate with their length of service had been analyzed.

Results Ninety-two workers in the noise exposure group were detected as hearing loss. The detection rate was 25.6%, which is higher than that in the control group (P < 0.05). There was an increasing tendency of hearing loss with increase in length of service(P < 0.05); differences in the distribution of abnormal rate of ECG, blood pressure in every group with length of service had no statistical significance(P>0.05). The risk of male and female hearing loss was not statistically different (P>0.05).

Conclusions There exist serious occupational noise hazards in the railway systems. In order to reduce the incidence of occupational noise deafness, the working environment should be improved. In the mean while, the individual protection and coating should be strengthened.