Air admittance vent

{
  "id": "MLC-T-IND-000126",
  "term": "Air admittance vent",
  "field": "Industrial and trades",
  "definition": "A one-way mechanical valve that allows air to enter a plumbing drainage system when negative pressure occurs, preventing the siphoning of water from fixture traps. It opens to equalize pressure within the drain pipes, then closes to prevent sewer gases from escaping into the building. This device serves as an alternative to conventional vent stacks, particularly in island sinks or remote fixtures.",
  "synonyms": [
    "AAV",
    "mechanical vent",
    "mechanical waste vent",
    "mechanical sewer vent"
  ],
  "subject": "Plumbing",
  "see_also": [
    "AAV"
  ],
  "references": [
    "Drain-waste-vent system (Wikipedia)"
  ],
  "translations": {
    "de": "Luftzuführventil",
    "es": "válvula de admisión de aire",
    "fr": "reniflard à membrane"
  },
  "url": "https://mlchart.com/terminology/industrial/air-admittance-vent/"
}