2家核电企业氨化装置加注设施改进前后的职业健康风险评估  

Occupational risk assessment levels before and after improvement on fueling devices in ammoniation facilities from 2 nuclear plants

作　　者：董一文[1] 康宁[1] 王鑫[1] 边洪英[1] 刘晓旭 汉锋[1] 叶萌[1] Dong Yiwen;Kang Ning;Wang Xin;Bian Hongying;Liu Xiaoxu;Han Feng;Ye Meng(Department of Occupational Epidemiology and Risk Assessment,National Institute for Occupational Health and Poison Control,Chinese Center for Disease Control and Prevention,Beijing 100050,China)

机构地区：[1]中国疾病预防控制中心职业卫生与中毒控制所职业流行病学与风险评估室,北京100050

出　　处：《卫生研究》2022年第6期911-917,共7页Journal of Hygiene Research

摘　　要：目的对2家核电厂(X与Y)氨化装置设施改进前后氨接触岗位劳动者职业健康风险评估风险等级的变化开展评估。方法通过职业卫生现场调查,了解氨化装置加注设施改进前(2015年)后(2017年)的更新变化,识别氨接触岗位及工作内容、收集防护措施及个体防护用品等信息。对涉及场所开展短时间接触浓度C_(STE)并计算10种氨接触岗位的8 h时间加权平均接触浓度C_(TWA);测定场所的事故通风量(m^(3)/h)及通风换气次数(次/h);根据GBZ/T 298—2017中的半定量综合指数风险评估模型和定量非致癌风险评估模型对装置改进前后液氨接触岗位的风险等级进行评定。结果改进设施后发现如下改变:(1)由原来的钢罐堆积存放方式改为金属加压密封罐常态化备存,减少人员接触频次;(2)加注自动一体化,装置顶部增设事故通风口,附近安置联动氨报警装置并设定预报值;(3)开启加药间侧门维持自然通风。由此,设施改进前X厂化学分析工程师、化学采样工程师、3#机中核维修工;Y厂1#机常规岛现操工、2#及运行现操工所在场所的C_(STE)已超限值水平的结果在改进后均得到改善,10种岗位所在场所C_(STE)和岗位C_(TWA)均符合限值要求。改进后各岗位接触场所中氨的C_(STE)显著低于改进前水平(Z=10.856,P<0.001);改进后10种岗位所在现场作业场所内的通风换气次数在13~30.9次/h,符合标准要求且相比于改进前差异具有统计学意义(Z=11.670,P<0.001)。相关性分析显示,改进前C_(STE)与场所通风换气次数间具有一般程度的负相关性(r=-0.39,P<0.05),改进后二者无显著相关性(r=-0.051,P>0.05);10种氨接触岗位在半定量风险评估模型应用时,化学分析工程师等大多数岗位在改进设施后呈现出风险等级下调(Z=1.345,P<0.05),3#机中核维修工、4#机运行现操工等岗位在设施改进后出现风险等级上调或维持不变,这可能与改进后个别岗位劳动者OBJECTIVE To evaluate and compare possible changes of individual health risk levels for ammonia exposed positions from ammoniation facilities in 2 nuclear power plants(X and Y)through occupational risk assessment models(OHRA)before and after devices improvement.METHODS This study tried to understand the improvement of fueling devices in ammoniation facilities,to identify the ammonia exposed positions and their working content,to collect information on protective measures and personal protective equipment situation through on-sites survey and detailed records of work days.Next,detection on C_(STE) of ammonia at different worksites and C_(TWA) of 10 involved positions were conducted,fresh air requirement and ventilation air changing rates were calculated through wind speed detection or collected directly.Finally,a semiquantitative comprehensive index model and a quantitative non-carcinogenic model from standard GBZ/T 298—2017 were utilized to assess risk levels before and after improvement.RESULTS After devices improvement,a series of innovations were observed,followed by:(1)ammonia steal tanks in stacking storage were replaced by metal pressure sealing tanks for reduction of exposure frequency and long time storage.(2)manual filling pattern was totally substituted by automatic filling devices with new installed ventilation systems and alarming apparatus.(3)increasing ventilation effect by doors opening when ammonia was filling.In this regard,conentration levels(C_(STE))referred to positions of chemical analysis engineers,chemical sampling engineers,nuclear maintenance workers at 3#unit from X,and regular island operators at 1#unit,patrolling operators at 2#unit from Y were declined to qualified levels after improvement from unqualified levels before that,and significant difference of C_(STE) detected before and after improvement were found statistically(Z=10.856,P<0.001).C_(TWA) were all within the qualified ranges before and after improvement for relatively short cumulative exposure time.Moreover,the ventilatio

关 键 词：氨 氨化装置 设施改进 通风换气次数 半定量综合指数风险评估模型 定量非致癌风险评估模型 

分 类 号：R13[医药卫生—劳动卫生]