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Data Validation & Laboratory Quality Assurance for Region 9

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In all hazardous site investigations, it is essential to know the quality of the data used for decision-making purposes. The process of generating data of known quality:
  • Begins in the planning stages when data quality objectives (DQOs) are established
  • Continues during sample collection activities and laboratory analysis
  • Is re-evaluated when validating the analytical data
  • Is finalized as part of the data quality assessment process

Validation of data requires that appropriate quality assurance and quality control (QA/QC) procedures be followed, and that adequate documentation be included for all data generated both in the laboratory and in the field. Professionals trained in data validation procedures review this information, "flag" data with qualifiers when QA/QC criteria are not met, and prepare the data validation report.

The documents presented are used to evaluate the quality of laboratory-generated analytical data

Evaluation of Laboratory Data Quality

Laboratory Quality Assurance

  • National Laboratory Accreditation ProgramExit
    A voluntary association of State and Federal agencies to establish and promote mutually acceptable performance standards for the operation of environmental laboratories.
  • Drinking Water Laboratory Certification Program
    EPA’s Office of Water implements the Drinking Water Laboratory Certification Program in partnership with EPA Regions and States. Laboratories must be certified by EPA or the State to analyze drinking water samples for compliance monitoring.

State Laboratory Certification Programs

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