Frequent Questions

Differences in quality control (QC), preservation, and holding time recommendations among SW-846 parts.

When there are differences in the quality control (QC) recommendations between Chapter One, a general method (e.g. 8000), and a determinative method (e.g. 8082), what is the proper precedence? Would recommendations for preservation and holding time follow the same precedence as QC?


The precedence for holding time and preservation is the same as that for QC. According to Chapter Two of SW-846, QC guidance specific to a given analytical technique (e.g., extraction, cleanup, sample introduction, or analysis) may be found in general methods 3500, 3600, 5000, 7000, and 8000.

When inconsistencies exist between the information in a chapter, a general method, or a specific method, method-specific QC criteria take precedence over both criteria found in the general method and those criteria given in Chapter One. QC criteria in general methods take precedence over the criteria in Chapter One.

Other Categories: QA/QC, General

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