锤锻与织布噪声对听力损害的比较研究

COMPARATIVE STUDY ON HEARING LOSS INDUCED BY DROP-FORGING AND WEAVING NOISE

选133名锤锻工和95名织布工为研究对象。现场噪声参数比较结果:锤锻声最大线性峰值(122.6～142.4dB)和峰值的变化以及A计权慢档均方根值(L_(AS))的全距,均明显大于织布声;峰值因数(L_(AP)—L_(AS))分布也较织布声宽;但锤锻工平均日接噪时间(2.4小时)明显短于织布工。根据锤锻与织布工4kHz实测和预期噪声性永久听阈移中值(N_0.50)间的比较及两工种间实测N_0.50的比较结果,均未见明显差异;而锤锻工不同的累积接噪剂量与4kHz的N_0.50之间有显著相关。看来锤锻噪声对工人听力的损害,尚符合等能量假说原理。

The 133 drop-forgers and 95 weavers were selected as subjects for the study. The comparative results of noise parameter in the field were: The maximum linear peak (122.6-142.4dB) , variability of peak and total range of A-weighted root-mean-square level with slow time constant (LAS) in the drop-forging noise were evidently greater than those in the weaving noise; the distribution of crest factor (LAP-LAS) for the drop-forging noise was wider than that for the weaving noisei but the mean time of noise exposure per day (2.4h) for the drop-forger was obviously shorter than that for the weaver. According to the comparative results of the measured and potential medians of noise-induced permanent threshold shift (N0.50) at 4kHz as well as the measured N0.50 between the drop-forgers and the weavers, there were no significant differences. Moreover, the rank correlation between the different noise dose of cumulative exposure and N0.50 at 4kHz for the drop-forgers was significant. It seems that the hearing loss of workers induced by the drop-forging noise is primarily consistent with the principle of the equal energy hypothesis.