Reference Substance

{
  "id": "MLC-T-ENV-023513",
  "term": "Reference Substance",
  "field": "Environment",
  "definition": "1. Any chemical substance or mixture, or analytical standard, or material other than a test substance, feed, or water, that is administered to or used in analyzing the test system in the course of a study for the purposes of establishing a basis for comparison with the test substance for known chemical or biological measurements.[40 CFR 160.3 (CFR 2013)]\n\n2. Any chemical substance or mixture, analytical standard, or material other than engine/motor vehicle emissions and/or its carrier, that is administered to or used in analyzing the test system in the course of a study. A “reference substance” is used to establish a basis for comparison with the test atmosphere for known chemical or biological measurements, i.e., positive or negative control substance.",
  "references": [
    "40 CFR 792.3 (CFR 2013)",
    "40 CFR 79.63 (CFR 2013)"
  ],
  "url": "https://mlchart.com/terminology/environment/reference-substance/"
}