制造业典型工种噪声暴露特征及其听力损失评估研究

Characteristics of noise exposure and the assessment of hearing loss in manufacturing industries

目的观察13个典型工种的噪声暴露特征分布情况,评估ISO-1999对我国制造业工人永久性听阈位移(Noise-induced permanent threshold shift,NIPTS)的预测效果,为诊断和预防复杂噪声引起的职业性听力损失提供依据。方法通过横断面调查,选择1404名制造业工人为研究对象,研究听力损失和噪声暴露特征及流行病学分布,分析ISO-1999预测值与NIPTS实测值之间的差异,探究峰度与该差异之间的关系。结果本次调查的4个行业13个工种的1404名制造业工人中,平均噪声暴露水平为(88.6±6.7)dB(A),平均峰度为(68.9±110.9),噪声性高频听力损失患病率(The prevalence of high frequency noise-induced hearing loss,HFNIHL%)为35.6%,平均高频噪声性永久性听阈位移(Noise-induced permanent threshold shift at frequencies of 3,4,and 6 kHz,NIPTS_(346))为(24.2±13.0)dB HL。除织造工和纺纱工,其余各工种ISO-1999预测值与NIPTS实测值差异均有统计学意义(P<0.05);对峰度进行分层分析,NIPTS实测值和预测值之间均存在统计学差异(t_(1)=4.801,t_(2)=11.468,t_(3)=13.247,t_(4)=9.498,P<0.05);不同峰度的低估值之间存在统计学差异(F=5.082,P<0.05),随峰度的升高而增加。结论制造业接噪工种分布广泛,高噪声水平、长期暴露和噪声复杂的时域结构是NIHL的风险因素;不同工序噪声源产生独特的随时间变化而变化的噪声时域波形;ISO-1999低估了工人实际的听力损失,低估值随峰度的升高而增加。

Objective To observe the distribution of noise exposure characteristics of 13 typical industries.To evaluate the prediction effect of ISO-1999 on the permanent hearing threshold shif(t NIPTS)of manufacturing workers in China,and to provide evidence for diagnosing and preventing occupational hearing loss caused by complex noise.Methods Through a cross-sectional survey,1,404 manufacturing workers were selected to study the characteristics and epidemiological distribution of hearing loss and noise exposure,and the difference between the ISO-1999 predicted values and the NIPTS measured values was analyzed to explore the relationship between kurtosis and this difference.Results All of the 1404 manufacturing workers in 13 job types in 4 industries surveyed in this study,the average noise exposure level was(88.6±6.7)dB(A),the average kurtosis was(68.9±110.9),and 35.6%of workers suffered from High Frequency Noise-induced Hearing Loss(HFNIHL),The average Noise-Induced Permanent Threshold Shift at Frequencies of 3,4,and 6 kHz(NIPTS_(346))is(24.2±13.0)dB HL.The complex noise waveform is significantly different from the Gaussian noise waveform.Except for weaving and spinning,the ISO-1999 predicted values and NIPTS actual values for all types were statistically different(P<0.05).There was a statistical difference between NIPTS actual and predicted values of different kurtosis(t_(1)=4.801,t_(2)=11.468,t_(3)=13.247,t_(4)=9.498,P<0.05),and there was a statistical difference between the underestimated of different kurtosis(F=5.082,P<0.05).Conclusion Manufacturing noise jobs are widely distributed,high noise levels,long-term exposure to noise and complex temporal structure of noise are risk factors for NIHL.ISO-1999 underestimates the actual hearing loss of workers,the underestimation increases with increasing kurtosis.