# Deluge System: Building Code Definition > How the IBC 2009, IFC 2009 define deluge system, where the wording differs, and which chapters depend on the term. - Canonical: https://harth.build/resources/glossary/deluge-system/ - Last updated: 2026-09-07 - Data source: Definitions quoted from the 2009 International Codes as transcribed in this site's building-codes collection, with the source chapter linked for each quotation. Usage counts are computed over the chapters hosted here, one copy per code. The [ICC code library](https://codes.iccsafe.org/codes) publishes the current model text and the [ICC adoption maps](https://www.iccsafe.org/advocacy/code-adoption-maps/) show which edition a jurisdiction has adopted; those sources control. ## Key facts | Fact | Value | | --- | --- | | Defined in | IBC 2009, IFC 2009 (2009 editions transcribed in this corpus) | | Primary source | IBC 2009 Fire Protection Systems (model text, not a jurisdiction's adopted text) | | Chapters using the term | 4 (counted across the codes hosted here) | | Wording identical across codes | No (compare before citing one code's wording under another) | ## Direct answer Deluge system is a defined term in the International Building Code (IBC) 2009, in Fire Protection Systems. The code's own words are: “A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same areas as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.” The IFC 2009 defines the same term with different wording, so the controlling text depends on which code governs the question in front of you — the comparison below sets the versions side by side. The term is used in 4 chapters of this corpus, most often in Definitions (IBC 2009), Fire Protection Systems (IBC 2009), Definitions (IFC 2009). These pages transcribe the 2009 model text; verify the definition against the edition and amendments your authority having jurisdiction has adopted. *Content and cited inputs reviewed by [Scott Barrington](https://nz.linkedin.com/in/barrington), Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.* ## What does this term mean? **Deluge System** — IBC 2009, Fire Protection Systems: > A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same areas as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto. ![Labeled code-term definition diagram: Deluge System: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/deluge-system/diagram-1344.webp) *How the IBC 2009, IFC 2009 define deluge system, where the wording differs, and which chapters depend on the term.* ## What must be verified before using this guidance? Two of the I-Codes in this corpus define **Deluge System**, and the wording is not identical — read the version that governs your question. | Code | Where it is defined | Definition | | --- | --- | --- | | IBC 2009 | [Fire Protection Systems](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/fire-protection-systems.md) | A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same areas as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto. | | IFC 2009 | [Fire Protection Systems](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/fire-protection-systems.md) | A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same area as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached there to. | ## Where deluge system is used in the code The term appears in 4 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next. | Chapter | Code | Mentions | | --- | --- | --- | | [Definitions](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/definitions.md) | IBC 2009 | 1 | | [Fire Protection Systems](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/fire-protection-systems.md) | IBC 2009 | 1 | | [Definitions](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/definitions.md) | IFC 2009 | 1 | | [Fire Protection Systems](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/fire-protection-systems.md) | IFC 2009 | 1 | ## The terms deluge system is built out of The definition above leans on 4 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what deluge system covers: - **[Piping System](https://harth.build/resources/glossary/piping-system.md)** — IRC 2009: All fuel piping, valves and fittings from the outlet of the point ofdeliveryto the outlets of the appliance shutoff valves. - **[Piping](https://harth.build/resources/glossary/piping.md)** — IRC 2009: Where used in this code, “piping” refers to either pipe or tubing, or both. - **[System](https://harth.build/resources/glossary/system.md)** — IFC 2009: An assembly of equipment consisting of a tank, container or containers, appurtenances, pumps, compressors and connecting piping. - **[Valve](https://harth.build/resources/glossary/valve.md)** — IRC 2009: A device used in piping to control the gas supply to any section of a system of piping or to an appliance. ## Deluge System: what to open, and in what order Every row is a document this term depends on. The [ICC code library](https://codes.iccsafe.org/codes) and the [ICC adoption maps](https://www.iccsafe.org/advocacy/code-adoption-maps/) cover the middle rows. | Check | Where | Confirmed | | --- | --- | --- | | Read the definition in the adopted IBC | Fire Protection Systems | | | Read the definition in the adopted IFC | Fire Protection Systems | | | Re-check the requirement that uses it | Definitions (IBC 2009) | | | Re-check the requirement that uses it | Fire Protection Systems (IBC 2009) | | | Re-check the requirement that uses it | Definitions (IFC 2009) | | | Re-check the requirement that uses it | Fire Protection Systems (IFC 2009) | | | Confirm the dependent definition | Piping System | | | Confirm the dependent definition | Piping | | | Confirm the dependent definition | System | | | Local amendment to any of the above | Jurisdiction's amendment list | | **A research aid, not a code determination.** The authority having jurisdiction decides which edition and which amendments apply. ## Where can you explore related guidance? - [Explore all glossary guidance](https://harth.build/resources/glossary.md) - [Piping System: Building Code Definition](https://harth.build/resources/glossary/piping-system.md) - [System: Building Code Definition](https://harth.build/resources/glossary/system.md) - [Piping: Building Code Definition](https://harth.build/resources/glossary/piping.md) - [Valve: Building Code Definition](https://harth.build/resources/glossary/valve.md) ## Sources and method Definitions quoted from the 2009 International Codes as transcribed in this site's building-codes collection, with the source chapter linked for each quotation. Usage counts are computed over the chapters hosted here, one copy per code. The [ICC code library](https://codes.iccsafe.org/codes) publishes the current model text and the [ICC adoption maps](https://www.iccsafe.org/advocacy/code-adoption-maps/) show which edition a jurisdiction has adopted; those sources control. ### Source links - [codes.iccsafe.org](https://codes.iccsafe.org/codes) - [iccsafe.org](https://www.iccsafe.org/advocacy/code-adoption-maps/) ## Frequently asked questions ### What is the code definition of deluge system? The International Building Code (IBC) 2009 defines it in Fire Protection Systems as: “A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same areas as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.” The 2009 model text is reproduced here; the definition that binds your project is the one in the edition your jurisdiction has adopted, as amended locally. ### Which parts of the code depend on deluge system? In this corpus the term is used across 4 chapters, led by Definitions in the IBC 2009. Those are the sections whose scope moves if the definition is amended locally, so read them together with Chapter 2 rather than on their own. ### What is a deluge system? In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Fire Protection Systems: “A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same areas as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.” It is defined in IBC 2009, IFC 2009. Because it is a defined term, whatever the adopted edition says it means is what every section using it means — so check Chapter 2 of that edition and any local amendment before relying on this wording. --- - Continue in Harth (open this topic in the Harth agent): https://app.harth.build/agent?context=%2Fresources%2Fglossary%2Fdeluge-system%2F - View this page in a browser: https://harth.build/resources/glossary/deluge-system/ - All resources for agents: https://harth.build/llms.txt