Closed-vent system

{
  "id": "MLC-T-ENV-005298",
  "term": "Closed-vent system",
  "field": "Environment",
  "term_source": "Closed-Vent System",
  "definition": "1. System that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow inducing devices that transport gas or vapor from an emission point to a control device. [40 CFR 63.1001 (CFR 2013)][40 CFR 63.1020 (CFR 2013)][40 CFR 63.1251 (CFR 2013)] [40 CFR 63.1361 (CFR 2013)]\n\n2. System that is not open to the atmosphere and that is composed of piping, ductwork, connections, and, if necessary, flow-inducing devices that transport emissions from a process unit or piece of equipment (e.g., pumps, pressure relief devices, sampling connections, open-ended valves or lines, connectors, and instrumentation systems) back into a closed system or into any device that is capable of reducing or collecting emissions.\n\n3. System that is not open to the atmosphere and is composed of piping, ductwork, connections, and if necessary, flow inducing devices that transport gas or vapor from an emission point to one or more control devices. If gas or vapor from regulated equipment is routed to a process (e.g., to a fuel gas system), the conveyance system shall not be considered a closed-vent system and is not subject to closed-vent system standards.\n\n4. System that is not open to the atmosphere and that is composed of hard-piping, ductwork, connections, and, if necessary, flow-inducing devices that transport gas or vapor from a piece or pieces of equipment to a control device or back to a process.\n\n5. System that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow inducing devices that transport gas or vapor from an emission point to a control device. A closed vent system does not include the vapor collection system that is part of any tank truck or railcar or the loading arm or hose that is used for vapor return. For transfer racks, the closed vent system begins at, and includes, the first block valve on the downstream side of the loading arm or hose used to convey displaced vapors.\n\n6. System that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow-inducing devices that transport gas or vapors from an emission point to a control device. This system does not include the vapor collection system that is part of some transport vehicles or the loading arm or hose that is used for vapor return. For transfer racks, the closed vent system begins at, and includes, the first block valve on the downstream side of the loading arm or hose used to convey displaced vapors.\n\n7. System that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow-inducing devices that transport gas or vapor from an emission point to a control device or back into the process.\n\n8. System that is not open to the atmosphere and is composed of piping, ductwork, connections, and, if necessary, flow inducing devices that transport gas or vapor from an emission point to a control device. Closed vent system does not include the vapor collection system that is part of any tank truck or railcar.\n\n9. System that is not open to the atmosphere and that is composed of piping, connections, and, if necessary, flow inducing devices that transport gas or vapor from a piece or pieces of equipment to a control device.\n\n10. System that is not open to the atmosphere and that is composed of hard-piping, ductwork, connections, and, if necessary, flow-inducing devices that transport natural gas from a piece or pieces of equipment to a control device or back to a process.",
  "subject": "Built environments",
  "references": [
    "40 CFR 63.441 (CFR 2018); 40 CFR 60.611a; 40 CFR 63.12005 (CFR 2013); 40 CFR 60.701a (CFR 2024); 40 CFR 63.101 (CFR 2024); 40 CFR 60.481b (CFR 2024)",
    "40 CFR 63.1156 (CFR 2013)",
    "40 CFR 63.1271 (CFR 2013)",
    "40 CFR 60.481 (CFR 2013); 40 CFR 60.481a (CFR 2013); 40 CFR 60.5430b (CFR 2024)",
    "40 CFR 65.2 (CFR 2013); 40 CFR 63.1082 (CFR 2013); 40 CFR 63.1101 (CFR 2013)",
    "40 CFR 63.2406 (CFR 2013)",
    "40 CFR 63.522 (CFR 2018)",
    "40 CFR 63.981 (CFR 2013)",
    "40 CFR 60.561 (CFR 2013)",
    "40 CFR 49.4163 (CFR 2013)"
  ],
  "url": "https://mlchart.com/terminology/environment/closed-vent-system/"
}