Building Code Glossary
Exhausted Enclosure: Building Code Definition
How the IBC 2009, IFC 2009 define exhausted enclosure, where the wording differs, and which chapters depend on the term.
On this page
Last updated September 7, 2026 · 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.
Direct answer
Exhausted enclosure is a defined term in the International Building Code (IBC) 2009, in Special Detailed Requirements Based on Use and Occupancy. The code's own words are: “An appliance or piece of equipment that consists ofa top, a back and two sides providing a means of local exhaust for capturing gases, fumes, vapors and mists. Such enclosures include laboratory hoods, exhaust fume hoods and similar appliances and equipment used to locally retain and exhaust the gases, fumes, vapors and mists that could” 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 9 chapters of this corpus, most often in Highly Toxic and Toxic Materials (IFC 2009), Semiconductor Fabrication Facilities (IFC 2009), Special Detailed Requirements Based on Use and Occupancy (IBC 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, Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.
What does this term mean?
Exhausted Enclosure — IBC 2009, Special Detailed Requirements Based on Use and Occupancy:
An appliance or piece of equipment that consists ofa top, a back and two sides providing a means of local exhaust for capturing gases, fumes, vapors and mists. Such enclosures include laboratory hoods, exhaust fume hoods and similar appliances and equipment used to locally retain and exhaust the gases, fumes, vapors and mists that could
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Exhausted Enclosure, and the wording is not identical — read the version that governs your question.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Special Detailed Requirements Based on Use and Occupancy | An appliance or piece of equipment that consists ofa top, a back and two sides providing a means of local exhaust for capturing gases, fumes, vapors and mists. Such enclosures include laboratory hoods, exhaust fume hoods and similar appliances and equipment used to locally retain and exhaust the gases, fumes, vapors and mists that could |
| IFC 2009 | Hazardous Materials-general Provisions | An appliance or piece of equipment which consists ofa top, a back and two sides providing a means of local exhaust for capturing gases, fumes, vapors and mists. Such enclosures include laboratory hoods, exhaust fume hoods and similar appliances and equipment used to retain and exhaust locally the gases, fumes, vapors and mists that could be released. Rooms or areas provided with general ventilation, in themselves, are not exhausted enclosures. |
Where exhausted enclosure is used in the code
The term appears in 9 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Highly Toxic and Toxic Materials | IFC 2009 | 65 |
| Semiconductor Fabrication Facilities | IFC 2009 | 54 |
| Special Detailed Requirements Based on Use and Occupancy | IBC 2009 | 35 |
| Exhaust Systems | IMC 2009 | 35 |
| Hazardous Materials-general Provisions | IFC 2009 | 23 |
| Fire Protection Systems | IBC 2009 | 6 |
| Compressed Gases | IFC 2009 | 4 |
| Definitions | IBC 2009 | 1 |
| Definitions | IFC 2009 | 1 |
The term in use
How the code actually writes about exhausted enclosure, quoted from the 2009 text hosted here:
Where an exhausted enclosure is used to increase maximum allowable quantity per controlarea or when the location of hazardous materials in exhausted enclosures is provided to comply with the provisions of Chapter 37, the exhausted enclosure shall be in accordance with Sections 2703.8.5.1 through 2703.8.5.3.
The fail-safe valve shall close when gas is detected at the permissible exposure limit (PEL) by a gas detection system monitoring the exhaust system at the point of discharge from the gas cabinet, exhausted enclosure, ventilated enclosure or gas room.
— IFC 2009, Highly Toxic and Toxic Materials
The terms exhausted enclosure is built out of
The definition above leans on 3 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what exhausted enclosure covers:
- Ventilation — IBC 2009: The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from, any space.
- Equipment — IRC 2009: All piping, ducts, vents, control devices and other components of systems other than appliances that are permanently installed and integrated to provide control of environmental conditions for buildings.
- Appliance — IRC 2009: Utilization equipment, normally built in standardized sizes or types, that is installed or connected as a unit to perform one or more functions such as clothes washing, air conditioning, food mixing, deep frying, etc.
Exhausted Enclosure: what to open, and in what order
Every row is a document this term depends on. The ICC code library and the ICC adoption maps cover the middle rows.
| Check | Where | Confirmed |
|---|---|---|
| Read the definition in the adopted IBC | Special Detailed Requirements Based on Use and Occupancy | |
| Read the definition in the adopted IFC | Hazardous Materials-general Provisions | |
| Re-check the requirement that uses it | Highly Toxic and Toxic Materials (IFC 2009) | |
| Re-check the requirement that uses it | Semiconductor Fabrication Facilities (IFC 2009) | |
| Re-check the requirement that uses it | Special Detailed Requirements Based on Use and Occupancy (IBC 2009) | |
| Re-check the requirement that uses it | Exhaust Systems (IMC 2009) | |
| Confirm the dependent definition | Ventilation | |
| Confirm the dependent definition | Equipment | |
| Confirm the dependent definition | Appliance | |
| 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
- Ventilation: Building Code Definition
- Equipment: Building Code Definition
- Appliance: Building Code Definition
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 publishes the current model text and the ICC adoption maps show which edition a jurisdiction has adopted; those sources control.
Source links
Frequently asked questions
What is the code definition of exhausted enclosure?
The International Building Code (IBC) 2009 defines it in Special Detailed Requirements Based on Use and Occupancy as: “An appliance or piece of equipment that consists ofa top, a back and two sides providing a means of local exhaust for capturing gases, fumes, vapors and mists. Such enclosures include laboratory hoods, exhaust fume hoods and similar appliances and equipment used to locally retain and exhaust the gases, fumes, vapors and mists that could” 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 exhausted enclosure?
In this corpus the term is used across 9 chapters, led by Highly Toxic and Toxic Materials in the IFC 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.
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