地铁和单轨列车司机噪声接触水平与听力损失情况比较

Comparison of noise exposure level and hearing loss between metro and monorail drivers

目的对比分析地铁和单轨列车司机职业性噪声接触水平和听力损失情况。方法采用方便抽样方法,选择1711名重庆市轨道列车司机为研究对象,其中地铁列车司机1123人,单轨列车司机588人。检测2组人群噪声接触水平和听力损失情况。结果地铁列车组司机接触的噪声8 h等效声级(L_(EX,8h))为(82.0±1.9)dB(A),超标率为7.14%(4/56);其中,As型、B2型地铁列车亚组司机接触的L_(EX,8h)分别为(81.9±2.0)和(82.3±1.9)dB(A),超标率分别为6.25%(2/32)和8.33%(2/24)。单轨列车司机接触的L_(EX,8h)为(76.7±1.3)dB(A),均未超过职业接触限值。地铁列车组司机L_(EX,8h)高于单轨列车组(P<0.01)。轨道列车司机听力损失检出率为2.34%(40/1711),高频听力异常检出率高于语频听力异常检出率(10.99%vs 2.81%,P<0.01),且语频听力异常、高频听力异常和听力损失检出率均随工龄的增加而增长(P值均<0.01)。As型和B2型地铁列车亚组司机高频听力异常检出率均高于单轨列车组司机(12.08%vs 5.44%,16.14%vs 5.44%,P值均<0.017)。结论地铁列车司机噪声接触水平高于单轨列车司机,高频听力异常情况更严重。

Objective To compare and analyze the difference of the occupational noise exposure level and hearing impairment between metro and monorail vehicle drivers.Methods A total of 1711 urban rail train drivers in Chongqing City were selected as research subjects using the convenience sampling method,with 1123 metro drivers and 588 straddle-type monorail vehicle drivers.The noise exposure level and hearing loss in the two groups were detected.Results The normalization of equivalent continuous A-weighted sound pressure level to a nominal 8 hours working day(L_(EX,8h))were(82.0±1.9),(81.9±2.0)and(82.3±1.9)dB(A)for the metro vehicle,As and B2 type metro vehicle drivers with the exceeding standard rate of 7.14%(4/56),6.25%(2/32)and 8.33%(2/24)respectively,and(76.7±1.3)dB(A)for the monorail drivers without exceeding the occupational exposure limits.The L_(EX,8h) of the metro vehicle drivers were significantly higher than that of the monorail drivers(P<0.01).The rate of hearing loss was 2.34%(40/1711)in the urban rail transit drivers,and the rate of high frequency hearing loss was higher than that of speech frequency hearing loss(10.99%vs 2.81%,P<0.01).The rate of high frequency hearing loss,speech frequency hearing loss and hearing loss increased with working years(all P<0.01).The rate of high frequency hearing abnormality of the As and B2 type metro vehicle drivers were both significantly higher than thatofthe monorail drivers(12.08%vs 5.44%,16.14%vs 5.44%,all P<0.017).Conclusion The noise exposure level and high frequency hearing abnormality in the metro vehicle drivers are more severe than that of those in the monorail vehicle drivers.