{"schemaVersion":1,"slug":"iec-duct-smoke-detector-plan-symbol","name":"Duct smoke detector plan symbol","kind":"symbol","abbreviation":"DSD","aliases":["duct detector","air duct smoke detector","duct sampling detector"],"category":"installation-communications","drawingTypes":["GA"],"referenceFamilies":["IEC"],"summary":"Plan symbol for a smoke detector sampling air from a ventilation duct, drawn on the duct with sampling tube.","description":["Duct smoke detectors sample air flowing in a ventilation duct through a sampling tube, so smoke can be detected and air handling shut down or dampers closed. Plans draw the detector housing on the duct with a line across the duct for the sampling tube.","They are coordinated with mechanical drawings and with the fire alarm cause and effect, since their main job is usually plant control. A remote indicator is often required where the detector is in a ceiling void.","The symbol does not prove the detector provides room protection. Duct detectors are not a substitute for area detection."],"readingNotes":["Check the duct and airflow direction on mechanical drawings.","Look for a remote indicator."],"drawingChecklist":["Show duct location.","Define plant shutdown action.","Provide remote indicator."],"distinction":"A room smoke detector protects a space; a duct detector monitors air in a duct for plant control.","facts":[{"label":"Primary purpose","value":"Shut down air handling or close dampers"},{"label":"Companion","value":"Remote indicator"},{"label":"Exact standard graphic","value":"Not reproduced here; confirm the form against IEC 60617 and the project legend"}],"references":[{"sourceId":"iec-diagrams","relevance":"IEC graphical symbol context for installation plans; independently drawn here."},{"sourceId":"pub-object-engineering-design","relevance":"Installation design context: life-safety systems are coordinated with the building electrical design."}],"related":["iec-smoke-detector-plan-symbol","ga-combined-fire-smoke-damper"],"artwork":"s28-iec-duct-smoke-detector-plan-symbol","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","symbolVariant":{"convention":"IEC","form":"Duct smoke detector","reference":"IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier."},"plainEnglish":{"title":"What does Duct smoke detector plan mean?","introduction":"Duct smoke detectors sample air flowing in a ventilation duct through a sampling tube, so smoke can be detected and air handling shut down or dampers closed. Plans draw the detector housing on the duct with a line across the duct for the sampling tube.","example":"They are coordinated with mechanical drawings and with the fire alarm cause and effect, since their main job is usually plant control. A remote indicator is often required where the detector is in a ceiling void.","drawings":"The symbol does not prove the detector provides room protection. Duct detectors are not a substitute for area detection.","terms":[{"name":"Schematic","meaning":"A drawing showing function and connections rather than physical appearance."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"IEC graphical symbols for diagrams","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/"},{"label":"Electrical installation design methodology and references","url":"https://www.electrical-installation.org/enwiki/General_rules_of_electrical_installation_design"}],"detail":"Plan symbol for a smoke detector sampling air from a ventilation duct, drawn on the duct with sampling tube. A room smoke detector protects a space; a duct detector monitors air in a duct for plant control.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/iec-duct-smoke-detector-plan-symbol","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/iec-duct-smoke-detector-plan-symbol.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"iec-diagrams","title":"IEC graphical symbols for diagrams","publisher":"IEC","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/","type":"standard","scope":"IEC 60617 and related symbol-design publications. Full database access requires a subscription.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"IEC graphical symbol context for installation plans; independently drawn here."},{"id":"pub-object-engineering-design","title":"Electrical installation design methodology and references","publisher":"Schneider Electric — Electrical Installation Guide","url":"https://www.electrical-installation.org/enwiki/General_rules_of_electrical_installation_design","type":"manufacturer","scope":"Public design context. No universal working clearance, equipment dimension or project compliance conclusion is asserted.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Installation design context: life-safety systems are coordinated with the building electrical design."}]}