Supplemental Gas

{
  "id": "MLC-T-ENV-027302",
  "term": "Supplemental Gas",
  "field": "Environment",
  "definition": "1. Any gaseous streams that are not defined as process vents, or closed-vent systems from wastewater management and treatment units, storage tanks, or equipment components and that contain less than 50 ppmv TOC, as determined through process knowledge, that are introduced into vent streams or manifolds. Air required to operate combustion device burner(s) is not considered supplemental gas.\n\n2. Any nonaffected gaseous streams (streams that are not from process vents, storage vessels, equipment or waste management units) that contain less than 50 ppmv TOC and less than 50 ppmv total HCl and chlorine, as determined through process knowledge, and are combined with an affected vent stream. Supplemental gases are often used to maintain pressures in manifolds or for fire and explosion protection and prevention. Air required to operate combustion device burner(s) is not considered a supplemental gas.\n\n3. Air that is added to a vent stream after the vent stream leaves the unit operation. Air that is part of the vent stream as a result of the nature of the unit operation is not considered supplemental gases. Air required to operate combustion device burner(s) is not considered supplemental gases.",
  "references": [
    "40 CFR 63.1251 (CFR 2013)",
    "40 CFR 63.1361 (CFR 2013)",
    "40 CFR 63.2550 (CFR 2013)"
  ],
  "url": "https://mlchart.com/terminology/environment/supplemental-gas/"
}