Quality Control Sample

{
  "id": "MLC-T-ENV-022894",
  "term": "Quality Control Sample",
  "field": "Environment",
  "definition": "1. An uncontaminated sample matrix spiked with known amounts of analytes from a source independent of the calibration standards. Generally used to establish intra- laboratory or analyst-specific precision and bias or to assess the performance of all or a portion of the measurement system.\n\n2. Any sample utilized by the analyst to check measurement conditions, whose measurement is expected to fall within specific acceptance criteria or control limits.\n\n3. A solution of method analytes of known concentrations that is used to fortify an aliquot of Laboratory Reagent Blank (LRB) or sample matrix. The QCS is obtained from a source external to the laboratory is different from the source of calibration standards. It is used to check laboratory performance with externally prepared test materials. This is a Performance Evaluation Sample in other arenas. (ORD)\n\n4. An uncontaminated sample matrix spiked with known amounts of analytes from a source independent from the calibration standards. It is generally used to establish intra-laboratory or analyst specific precision and bias or to assess the performance of all or a portion of the measurement system. This does not include matrix spikes or laboratory duplicates, which are also QC samples.\n\n5. A sample made from standards or matrix and used to verify acceptability of the results for an analytical batch. Examples of quality control samples are method blanks, laboratory duplicates, laboratory control samples, and matrix spikes.\n\n6. A mid-level standard prepared from a second source standard or prepared from a source of standards different from the source of calibration standards. The purpose of the QCS is to verify the integrity of the primary calibration standards. A QCS is analyzed during the initial demonstration of capability (IDC) and following each initial calibration (at a minimum quarterly) thereafter.",
  "abbreviation": "QC Sample",
  "synonyms": [
    "QCS"
  ],
  "subject": "Policy and guidance",
  "references": [
    "Guidance for Quality Assurance Project Plans",
    "Great Lakes Quality Mgmt Plan Glossary",
    "Forum on Environmental Measurements (FEM) Glossary",
    "40 CFR 63.11426 (2023)"
  ],
  "url": "https://mlchart.com/terminology/environment/quality-control-sample/"
}