【国外标准】 Standard Practice for Estimation of Holding Time for Water Samples Containing Organic Constituents (Withdrawn 2006)

1.1 This practice describes the means of estimating the period of time during which a water sample can be stored after collection and preservation without significantly affecting the accuracy of analysis. 1.2 The maximum holding time is highly matrix-dependent and is also dependent on the specific analyte of interest. Therefore, water samples from a specific source must be tested to determine the period of time that sample integrity is maintained by standard preservation practices. 1.3 In those cases where it is not possible to analyze the sample immediately at the time of collection, this practice does not provide information regarding degradation of the constituent of interest or changes in matrix that may occur from the time of sample collection to the time of the initial analysis. 1.4 This practice does not provide information regarding holding time for concentration of analyte less than one order of magnitude above the criterion of detection. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.