Quality Assurance and Quality Control

Many studies have shown that analytical reserves are often subjected to serious errors particularly at low concentrations encountered in the environmental samples in fact the errors may be so large that the validity and the action taken regarding the management of environment may become questionable nutrients like nitrogen and phosphorus in very small concentration also can cause eutrophication of water bodies.
an analytical quality control exercise conducted by USEPA showed a wide variation and results when the identical samples were taken for analysis by 22 Labs. This chapter throws light on various aspects of quality analysis program like sample control and documentation, standard analytical procedures, analyst qualification, equipment maintenance calibration procedures and analytical quality control.