摘要
目的估算核燃料元件生产线六氟化铀(UF_6)气体少量泄漏情况下泄漏量,评估其对人体的健康影响。方法假设的事故模型为UF_6气化岗位容器阀门与管道之间的软管破损导致UF_6泄漏,气溶胶抵达工作人员时间需8 s,工作人员撤离气化间需1~4 min。通过气体泄漏估算公式和内照射待积有效剂量(E)估算公式,估算UF_6气体泄漏量、工作人员吸入铀和氟化氢的量,评估UF_6所致辐射危害、肾损害和氟化氢所致人体健康影响情况。结果假设工作人员撤离需1 min时UF_6气体1 min内泄漏量为88.20 g,含铀量约为59.64 g,E为0.40 mSv,预计铀吸入量为4.57 mg,氟化氢的吸入平均质量浓度约为90.33 mg/m^3(低于其立即威胁生命或健康的急性危险浓度136.93 mg/m^3),此时产生人体健康影响的程度较小。在工作人员撤离所需时间为2~4 min时,UF_6泄漏量为176.40~352.80 g,含铀量为119.27~238.54 g,E为0.81~1.62 mSv,此时UF_6所致辐射危害较小;但预计铀吸入量为9.26~18.51 mg,可导致短暂肾脏损害;而撤离时间为2、3、4 min时氟化氢平均吸入质量浓度分别为83.98、82.03和81.03 mg/m^3,接近或高于其急性危险浓度(分别为96.82、79.06和68.46 mg/m^3),可导致急性氟化氢中毒,甚至猝死。结论 UF_6泄漏事故发生时,应尽快在1 min中内撤离。若撤离所需时间超过2 min,增加发生肾脏损害、急性氟化氢中毒和猝死的风险。
Objective To estimate the amount of the uranium hexafluoride（ UF6） gas leakage in a nuclear fuel element production line,and assess the effect of the leakage on human health. Methods The hypothetical accident model was set that the leakage of UF6 was caused by the hose breakage between valve and pipeline in the UF6 vaporization process. It took8 seconds for the aerosol to get to the staffs and the staffs needed 1-4 minutes to evacuate. The leakage amount of UF6 gas and intake of uranium and hydrogen fluoride（ HF） were calculated using the estimation formula of gas leakage and internal radiation dose. Its influence on human health was assessed. The radiation hazard and kidney damage induced by the UF6 exposure,and the chemical hazards to human health caused by HF inhalation were assessed. Results It is supposed that the staffs need 1 minute to evacuate,the leakage amount of UF6 within 1 minute is 88. 20 g,and the uranium content is about 59. 64 g. The committed effective dose of internal exposure is 0. 40 mSv. The predicted intake of uranium is4. 57 mg. The average inhalation concentration of HF is calculated to be about 90. 33 mg /m^3,which is below the promptly life-threatening or health-threatening acute concentration（ 136. 93 mg /m^3）. In this case,it has little impact on human health. If the staffs need 2-4 minutes to evacuate,the leakage amount of UF6 within 1 minute is 176. 40-352. 80 g,and the uranium content is about 119. 27-238. 54 g,the committed effective dose of internal exposure is 0. 81-1. 62 mSv. In that case,it has a small radiation hazard caused by UF6. However,the predicted intake of uranium is 9. 26-18. 51 mg,which might lead to a short-term kidney damage. If the evacuation time is 2,3 or 4 minutes,the average inhaled mass concentrations of HF are 83. 98,82. 03 and 81. 03 mg /m^3,respectively,which are close to or higher than the immediately dangerous to life or health concentration（ 96. 82,79. 06 and 68. 46 mg /m^3,respectively）,and it might lead to an acute HF poisoning,even sudden death. Conclusion When the UF6 leakage accident happens,the staffs should evacuate in 1minute. If the evacuation time is longer than 2 minutes,it will increase the risk of kidney damage,acute HF poisoning and sudden death.
出处
《中国职业医学》
CAS
北大核心
2016年第4期467-470,474,共5页
China Occupational Medicine
关键词
六氟化铀
气体
泄漏量
铀
氟化氢
健康影响
Uranium hexafluoride
Gas
Leakage amount
Uranium
Hydrogen fluoride
Health effect
