# Air Conditioning: Building Code Definition

> How the IMC 2009 define air conditioning, where the wording differs, and which chapters depend on the term.

- Canonical: https://harth.build/resources/glossary/air-conditioning/
- 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 | IMC 2009 (2009 editions transcribed in this corpus) |
| Primary source | IMC 2009 Definitions (model text, not a jurisdiction's adopted text) |
| Chapters using the term | 10 (counted across the codes hosted here) |
| Wording identical across codes | Single code (compare before citing one code's wording under another) |

## Direct answer

Air conditioning is a defined term in the International Mechanical Code (IMC) 2009, in Definitions. The code's own words are: “The treatment of air so as to control simultaneously the temperature, humidity, cleanness and distribution of the air to meet the requirements of a conditioned space.” No other I-Code in this corpus defines it, so the IMC 2009 definition is the one to work from. The term is used in 10 chapters of this corpus, most often in Building Planning (IRC 2009), Elevators and Conveying Systems (IBC 2009), Fuel Gas (IRC 2009). These pages transcribe the 2009 model text; verify the definition against the edition and amendments your authority having jurisdiction has adopted. Record the jurisdiction, the adopted edition, the application date and any local amendment that rewrites the definition before you use it on a live project, because a term redefined by amendment changes every requirement that depends on it.

*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?

**Air Conditioning** — IMC 2009, Definitions:

> The treatment of air so as to control simultaneously the temperature, humidity, cleanness and distribution of the air to meet the requirements of a conditioned space.

![Labeled code-term definition diagram: Air Conditioning: Building Code Definition](https://efwwel0vyt9vy5so.public.blob.vercel-storage.com/images/glossary/air-conditioning/diagram-1344.webp)

*How the IMC 2009 define air conditioning, where the wording differs, and which chapters depend on the term.*

## What must be verified before using this guidance?

**Air Conditioning** is defined once in this corpus, in the [Definitions](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/definitions.md) chapter of the International Mechanical Code (IMC) 2009:

> The treatment of air so as to control simultaneously the temperature, humidity, cleanness and distribution of the air to meet the requirements of a conditioned space.

## Where air conditioning is used in the code

The term appears in 10 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.

| Chapter | Code | Mentions |
| --- | --- | --- |
| [Building Planning](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/building-planning.md) | IRC 2009 | 7 |
| [Elevators and Conveying Systems](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/elevators-and-conveying-systems.md) | IBC 2009 | 6 |
| [Fuel Gas](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/fuel-gas.md) | IRC 2009 | 5 |
| [Building Services and Systems](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/building-services-and-systems.md) | IFC 2009 | 3 |
| [Roof Assemblies and Rooftop Structures](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/roof-assemblies-and-rooftop-structures.md) | IBC 2009 | 1 |
| [Definitions](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/definitions.md) | IMC 2009 | 1 |
| [Scope and Administration](https://harth.build/resources/building-codes/us-states/new-hampshire/imc-2009/scope-and-administration.md) | IMC 2009 | 1 |
| [Storm Drainage](https://harth.build/resources/building-codes/us-states/new-hampshire/ipc-2009/storm-drainage.md) | IPC 2009 | 1 |
| [Definitions](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/definitions.md) | IRC 2009 | 1 |
| [Electrical Definitions](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/electrical-definitions.md) | IRC 2009 | 1 |

### The term in use

How the code actually writes about air conditioning, quoted from the 2009 text hosted here:

> Wires or cables that provide normal and standby power, control signals, communication with the car, lighting, heating, air conditioning' ventilation and fire-detecting systems to fire service access elevators shall be protected by construction having a minimum I-hour fire-resistance rating or shall be circuit integrity cable having a minimum I-hour fire-resistance rating.

— [IBC 2009 §3007.7.1](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/elevators-and-conveying-systems.md)

> Air conditioning appliances shall be tested in accordance with ANSI Z21.40.1 or ANSI Z21.40.2 and shall be installed in accordance with the manufacturer's installation instructions.

— [IRC 2009 §G2449.1](https://harth.build/resources/building-codes/us-states/maryland/irc-2009/fuel-gas.md)

> Where standby power is connected to elevators, the machine room ventilation or air conditioning shall be connected to the standby power source.

— [IFC 2009 §604.2.18.4](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/building-services-and-systems.md)


## The terms air conditioning is built out of

The definition above leans on 2 other defined terms. Each carries its own code definition, and a local amendment to any of them changes what air conditioning covers:

- **[Conditioned Space](https://harth.build/resources/glossary/conditioned-space.md)** — IRC 2009: For energy purposes, space within a building that is provided with heating and/or cooling equipmentor systems capable of maintaining, through design or heat loss/gain, 50°F (IO°C) during the heating season and 85°F (29°C) during the cooling season, or communicates directly …
- **[Control](https://harth.build/resources/glossary/control.md)** — IRC 2009: A manual or automatic device designed to regulate the gas, air, water or electrical supply to, or operation of, a mechanical system.

## Air Conditioning: 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 IMC | Definitions | |
| Re-check the requirement that uses it | Building Planning (IRC 2009) | |
| Re-check the requirement that uses it | Elevators and Conveying Systems (IBC 2009) | |
| Re-check the requirement that uses it | Fuel Gas (IRC 2009) | |
| Re-check the requirement that uses it | Building Services and Systems (IFC 2009) | |
| Confirm the dependent definition | Conditioned Space | |
| Confirm the dependent definition | Control | |
| 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)
- [Conditioned Space: Building Code Definition](https://harth.build/resources/glossary/conditioned-space.md)
- [Control: Building Code Definition](https://harth.build/resources/glossary/control.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 air conditioning?

The International Mechanical Code (IMC) 2009 defines it in Definitions as: “The treatment of air so as to control simultaneously the temperature, humidity, cleanness and distribution of the air to meet the requirements of a conditioned space.” 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 air conditioning?

In this corpus the term is used across 10 chapters, led by Building Planning in the IRC 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 the definition of air conditioning?

In the 2009 I-Codes hosted here it is a defined term rather than a description. The IMC 2009 states, in Definitions: “The treatment of air so as to control simultaneously the temperature, humidity, cleanness and distribution of the air to meet the requirements of a conditioned space.” It is defined in IMC 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%2Fair-conditioning%2F
- View this page in a browser: https://harth.build/resources/glossary/air-conditioning/
- All resources for agents: https://harth.build/llms.txt