气溶胶总放射性物质留样复测

Discussion on Retest of Total Radioactivity for Remaining Aerosol Sample

目的探讨气溶胶总放射性物质留样复测的可行性。方法样品前处理参照《辐射环境监测技术规范》(HJ 61-2001),制样测量参照《水中总α放射性浓度的测定厚样法》(EJ/T 1075-1998)、《水中总β放射性测定蒸发法》(EJ/T 900-1994),对气溶胶总放射性物质随时间变化进行监测分析。结果气溶胶放置120 h后总放射性物质基本保持不变,32 d后总α放射性物质留样复测相对偏差达到34.7%,接近质量计划要求的相对偏差控制限,以后呈线性增长。结论留样复测并不是最恰当的常规质量控制手段,实验室间比对更合理。

Objectives To discuss the feasibility on retest of gross radioactivity for the remaining aerosol samples.Methods The Technical criteria for radiation environmental monitoring(HJ/T 61-2001)was referenced for sample pretreatment,the Water quality-determination of gross alpha activity-thick source method(EJ/T 1075-1998)and Water quality-Determination of gross beta activity-evaporation method(EJ/T 900-1994)were referenced for sample preparation and measurement,then analyzed the variation of gross radioactivity in aerosol as a function of time.Results The gross radioactivity remained stable after the samples were placed for 120 h,but the relative deviation of gross α activity of retest of the remaining samples reached 34.7%after 32 days,which was close to the limit value in terms of the quality requirement,and it increased linearly after that.Conclusions Retest of the remaining samples might not be the most appropriate routine quality control method.