Field blank

{
  "id": "MLC-T-ENV-010925",
  "term": "Field blank",
  "field": "Environment",
  "term_source": "Field Blank",
  "definitions": [
    "1. Any sample submitted from the field identified as a blank.\n\n2. A clean analyte-free sample which is carried to the sampling site and then exposed to sampling conditions, returned to the laboratory, and treated as an environmental sample. This blank is used to provide information about contaminants that may be introduced during sample collection, storage, and transport.\n\n3. Blank prepared in the field by filling a clean container with pure de-ionized water and appropriate preservative, if any, for the specific sampling activity being undertaken. {ORD} {OPP} {OSWER} {OAR/OAQPS} {OECA} {ORCR}\n\n4. An aliquot of reagent water or other reference matrix that is placed in a sample container in the field, and treated as a sample in all respects, including exposure to sampling site conditions, storage, preservation, and all analytical procedures. The purpose of the field blank is to determine if the field or sample transporting procedures and environments have contaminated the sample. {OW/EAD} {ORCR}\n\n5. Blank prepared in the field by filling a clean container with pure de-ionized water and appropriate preservative, if any, for the specific sampling activity being undertaken.\n\n6. An aliquot of reagent water or other reference matrix that is placed in a sample container in the field, and treated as a sample in all respects, including exposure to sampling site conditions, storage, preservation, and all analytical procedures. The purpose of the field blank is to determine if the field or sample transporting procedures and environments have contaminated the sample.\n\n7. In radiochemistry, samples preserved with reagents that are not provided by the laboratory. These should be accompanied by a radioactive-free field blank sample that is preserved in the same manner as the submitted samples. The field blank is a volume of blank matrix that is placed in a clean sample container, preserved in the field, shipped along with the samples and subjected to the same analytical procedures as the samples. A sample of the preservative should also accompany the field samples to determine whether it contributes any contamination.\n\n8. A sample used to identify and estimate contamination immediately before and after sampling (evaluation of protocols), during sample shipment, and for samples awaiting measurement in the laboratory.",
    "(radiochemistry) Samples preserved with reagents that are not provided by the laboratory. These should be accompanied by a radioactive-free field blank sample that is preserved in the same manner as the submitted samples. The field blank is a volume of blank matrix that is placed in a clean sample container, preserved in the field, shipped along with the samples and subjected to the same analytical procedures as the samples. A sample of the preservative should also accompany the field samples to determine whether it contributes any contamination. {OW/TSC}"
  ],
  "subject": "Policy and guidance",
  "references": [
    "Underground Storage Tank Sites Guide Glossary",
    "Guidance for Quality Assurance Project Plans",
    "Forum on Environmental Measurements (FEM) Glossary",
    "EPA Office of Research and Development; Forum on Environmental Measurements (FEM) Glossary",
    "EPA/600/R-14/027"
  ],
  "url": "https://mlchart.com/terminology/environment/field-blank/"
}