上海市奉贤区2009—2011年16家企业电焊烟尘浓度的监测结果

目的了解上海市奉贤区2009—2011年16家企业电焊作业环境的职业危害情况,为改善作业环境,保护作业人员健康,提供科学依据。方法采用定点多次(3次)短时间采样法估算时间加权平均(TWA)浓度,和个体(不定点)采样实测TWA浓度。结果电焊烟尘总平均浓度为3.18 mg/m3,定点采样电焊烟尘平均浓度为1.33 mg/m3,个体采样电焊烟尘平均浓度为3.80 mg/m3;电焊烟尘浓度总合格率为79.3%,定点合格率为85.7%,个体合格率为75.6%。接触电焊烟尘时间4 h与4 h总合格率比较显示,接触时间4 h电焊烟尘合格率定点与个体的差异有统计学意义(χ2=6.815,P0.01),接触4 h电焊烟尘总合格率定点与个体的比较,差异无统计学意义(χ2=0.046,P0.05)。定点接触时间4 h与4 h合格率比较,接触时间4 h电焊烟尘合格率差异有统计学意义(χ2=8.018,P0.01),个体接触时间4 h与4 h电焊烟尘合格率的比较,差异有统计学意义(χ2=24.05,P0.01)。对压力容器制造企业,进行桶内桶外工人电焊作业的电焊烟尘比较,合格率分别为41.67%和90.7%,桶内桶外合格率的差异有统计学意义(χ2=8.852,P0.01)。结论焊接工人接触时间的不同,测得电焊烟尘浓度也不同,随着作业时间延长,电焊烟尘浓度增高;桶内桶外测得电焊烟尘浓度也不同,电焊烟尘浓度桶内高于桶外,对工人接触时间的不同和环境不同,应采取不同作业时间和防护措施。

Monitoring results of welding fume concentrations in 16 enterprises of Fengxian District of Shanghai City from 2009-2011

[Objective]To investigate the occupational hazards in welding operation environment of 16 enterprises in Fengxian District of Shanghai City from 2009-2011,and provide scientific evidence for operation environment improvement and workers’ health protection.[Methods]Repeatedly(3 times) short time sampling method and personal sampling(unfixed) were adopted to estimate and measure the time weighted average(TWA) concentration.[Results] The total welding fume concentration was 3.18 mg/m3,the average concentration of area sampling welding fume was 1.33 mg/m3,and the average concentration of personal sampling welding fume was 3.80 mg/m3.The total qualified rate of welding fume concentration of was 79.3%,the area sampling qualified rate was 85.7% and personal sampling qualified rate was 75.6%.The comparison of total qualified rate of welding fumes exposure length >4 h and <4 h showed the difference between area sampling and personal sampling with exposure length >4 h was significant(χ2=6.815,P<0.01),while the difference <4 h was not significant(χ2=0.046,P>0.05).Comparing exposure to welding fumes qualified rate of area sampling >4 h and <4 h,the difference was statistically significant(χ2=8.018,P<0.01).The difference of qualified rate of personal sampling between exposure length>4 h and <4 h was significant(χ2=24.05,P<0.01).Comparing the welding fume concentrations inner head tank with external in the pressure vessel manufacturing enterprises,the qualified rates were 41.67% and 90.7% respectively,the difference was significant(χ2=8.852,P<0.01).[Conclusion]The concentrations of welding dust is significantly different between welding workers with different exposure length.With time extension,the welding fume concentration has increased.The welding fume concentration inner head tank is higher than that external.The different operation length and protective measures should be adopted according to workers with different exposure time and different operation environments.