# Pyrophoric: Building Code Definition

> How the IBC 2009, IFC 2009 define pyrophoric, where the wording differs, and which chapters depend on the term.

- Canonical: https://harth.build/resources/glossary/pyrophoric/
- 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 Use and Occupancy Classification (model text, not a jurisdiction's adopted text) |
| Chapters using the term | 10 (counted across the codes hosted here) |
| Wording identical across codes | No (compare before citing one code's wording under another) |

## Direct answer

Pyrophoric is a defined term in the International Building Code (IBC) 2009, in Use and Occupancy Classification. The code's own words are: “A chemical with an autoignition temperature in air, at or below a temperature of 130°F (54.4°C).” 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 10 chapters of this corpus, most often in Pyrophoric 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](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?

**Pyrophoric** — IBC 2009, Use and Occupancy Classification:

> A chemical with an autoignition temperature in air, at or below a temperature of 130°F (54.4°C).

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

*How the IBC 2009, IFC 2009 define pyrophoric, 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 **Pyrophoric**, and the wording is not identical — read the version that governs your question.

| Code | Where it is defined | Definition |
| --- | --- | --- |
| IBC 2009 | [Use and Occupancy Classification](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/use-and-occupancy-classification.md) | A chemical with an autoignition temperature in air, at or below a temperature of 130°F (54.4°C). |
| IFC 2009 | [Pyrophoric Materials](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/pyrophoric-materials.md) | A chemical with an autoignition temperature in air, at or below a temperature of 130° P (54°C). |

## Where pyrophoric 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 |
| --- | --- | --- |
| [Pyrophoric Materials](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/pyrophoric-materials.md) | IFC 2009 | 37 |
| [Semiconductor Fabrication Facilities](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/semiconductor-fabrication-facilities.md) | IFC 2009 | 33 |
| [Special Detailed Requirements Based on Use and Occupancy](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/special-detailed-requirements-based-on-use-and-occupancy.md) | IBC 2009 | 21 |
| [Definitions](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/definitions.md) | IFC 2009 | 7 |
| [Hazardous Materials-general Provisions](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/hazardous-materials-general-provisions.md) | IFC 2009 | 7 |
| [Use and Occupancy Classification](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/use-and-occupancy-classification.md) | IBC 2009 | 6 |
| [Electrical](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/electrical.md) | IBC 2009 | 2 |
| [Flammable Gases and Flammable Cryogenic Fluids](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/flammable-gases-and-flammable-cryogenic-fluids.md) | IFC 2009 | 2 |
| [Definitions](https://harth.build/resources/building-codes/us-states/maryland/ibc-2009/definitions.md) | IBC 2009 | 1 |
| [Compressed Gases](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/compressed-gases.md) | IFC 2009 | 1 |

### The term in use

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

> The storage and use of pyrophoric materials shall be in accordance with this chapter.

— [IFC 2009 §4101.1](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/pyrophoric-materials.md)

> Cabinets in fabrication areas containing pyrophoric liquids or Class 3 water-reactive liquids in containers or in amounts greater than ½ gallon (2 L) shall comply with Section 1805.2.3.4.

— [IFC 2009 §1803.3.9](https://harth.build/resources/building-codes/us-states/rhode-island/ifc-2009/semiconductor-fabrication-facilities.md)


## The terms pyrophoric is built out of

The definition above leans on 1 other defined term. Each carries its own code definition, and a local amendment to any of them changes what pyrophoric covers:

- **[Chemical](https://harth.build/resources/glossary/chemical.md)** — IFC 2009: An element, chemical compound or mixture of elements or compounds or both.

## Pyrophoric: 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 | Use and Occupancy Classification | |
| Read the definition in the adopted IFC | Pyrophoric Materials | |
| Re-check the requirement that uses it | Pyrophoric 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 | Definitions (IFC 2009) | |
| Confirm the dependent definition | Chemical | |
| 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)
- [Chemical: Building Code Definition](https://harth.build/resources/glossary/chemical.md)
- [Corrosive: Building Code Definition](https://harth.build/resources/glossary/corrosive.md)
- [Hazardous Materials: Building Code Definition](https://harth.build/resources/glossary/hazardous-materials.md)
- [Combustible Liquid: Building Code Definition](https://harth.build/resources/glossary/combustible-liquid.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 pyrophoric?

The International Building Code (IBC) 2009 defines it in Use and Occupancy Classification as: “A chemical with an autoignition temperature in air, at or below a temperature of 130°F (54.4°C).” 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 pyrophoric?

In this corpus the term is used across 10 chapters, led by Pyrophoric 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.

### What is the definition of pyrophoric?

In the 2009 I-Codes hosted here it is a defined term rather than a description. The IBC 2009 states, in Use and Occupancy Classification: “A chemical with an autoignition temperature in air, at or below a temperature of 130°F (54.4°C).” 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.

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