非稳态噪声工作场所噪声暴露测量与评价

目的]测量和评价非稳态噪声工作场所的8h等效连续A声级（LAeq.8h）、1min等效连续A声级（LAeq.8h）和全天等效声级估算值（LAeq.8h）。方法]采用个人声暴露计测量LAeq.8h，用声级计测量LAeq.8h。和每个时间段的噪声值，计算出全天的等效声级（LAeq.8h）。应用LAeq.8h和LAeq.8h、LAeq.8T分别测量某输油管道加工厂和某家用电器制造厂239名工人的个体噪声（接触）和相应作业场所噪声（暴露）水平。结果]两家工厂LAeq.8h均值分别为（89．7±3.8）dB（A）和（90．5±5．7）dB（A），分别高于LAeqT的（88．0±2．4）dB（A）和（89．2±3．6）dB（A）（P〈O．05或P〈0．01）。与LAeq.8h相比，LAeq.1min采样时间点存在抽样误差。绝大多数工作岗位的LAeq.1min与LAeq.8h均值差大于3dB（A），所有工作岗位的LAeq.8T均值与LAeq.8h均值差均小于3．0dB（A）。结论]LAeq.8h能反映在非稳态噪声工作场所工人实际接触噪声暴露水平，LAeq.T比较符合作业工人实际噪声接触水平LAeq.1min。会低估或高估工人噪声暴露水平。

Measurement and Evaluation on Workplace Non-Steady Noise Exposure

Objective ] To measure and evaluate the eight-hour continuous equivalent A-weighted sound levels （Lsoq.8h）, one-minute continuous equivalent A-weighted sound levels （LAeq.lmin）, and continuous equivalent A-weighted sound levels over a work day （LAeq.T） of non-steady noise at work. Methods ]LAeq.8h was determined by personal noise dosimeter. LAeq.1min was measured by environmental noise dosimeter. LAeq.T was calculated with LAb.1 min. A Total of 239 workers exposed to non-steady noise in a pipeline manufacturing factory and a household appliance factory were investigated using LAeq.8h. Workplace noise levels were measured using LAeq.1min and LAeq.T Results ] The averages of LAeq.8h in the two factories （89.7 ± 3.8）dB（A） and （90.5 ± 5.7）dB（A） ] were significantly higher than the averages of LAeq.T （88.0 ± 2.4） dB（A） and （89.2 ± 3.6） dB（A） （P 〈 0.05 or P 〈 0.01） ]. Sampling time errors of the values of LAeq.1min were observed as compared with the values of LAeq.8h. The differences between the mean values of LAeq.1min. and LAoq.Sh at most of the work locations were greater than 3 dB（A）. The differences between the mean values of LAeq.T and LAeq.Sh at all work locations were less than 3.0dB（A）. Conclusion ] LAeq.8h is able to measure the non-steady noise level of workers. LAeq.T reflects actual noise levels of workers. LAeq.lmin may underestimate or overestimate noise levels.