空白批内标准偏差和方法检出限的计算

环境分析化学中,尤其痕量分析时,方法检出限对于监测结果的报出很重要。检出限的确定常会涉及空白标准偏差的计算。通过对一典型案例剖析,指出一部分新制修订环境标准方法采用空白批间标准偏差计算检出限是不合理的。在求算检出限时应先判断批间是否存在显著性差异。

Calculation on Batch Standard Deviation of the Blank and Methods Detection Limit

In environmental analytical chemistry,especially trace analysis,the methods detection limit for the reported results of the monitoring is extremely important. Determination of the detection limit often involves with calculating the standard deviation of the blank. Based on the analysis of a typical case,it was pointed out that part of the revised environmental standard method of using the new system between batches blank to calculate the standard deviation of the detection limit was unreasonable. Before calculating the detection limit it is necessary to determine whether there are significant differences between batches.