Building Code Glossary
Gaseous Hydrogen System: Building Code Definition
How the IBC 2009 define gaseous hydrogen system, 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
Gaseous hydrogen system 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 assembly of piping, devices and apparatus designed to generate, store, contain, distribute or transport a nontoxic, gaseous hydrogen-containing mixture having at least 95-percent hydrogen gas by volume and not more than I-percent oxygen by volume. Gaseous hydrogen systems consist of items such as compressed gas containers, reactors and appurtenances, including pressure regulators, pressure relief …” No other I-Code in this corpus defines it, so the IBC 2009 definition is the one to work from. The term is used in 7 chapters of this corpus, most often in Motor Fuel-dispensing Facilities and Repair Garages (IFC 2009), Special Detailed Requirements Based on Use and Occupancy (IBC 2009), Special Fuel-burning Equipment (IRC 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?
Gaseous Hydrogen System — IBC 2009, Special Detailed Requirements Based on Use and Occupancy:
An assembly of piping, devices and apparatus designed to generate, store, contain, distribute or transport a nontoxic, gaseous hydrogen-containing mixture having at least 95-percent hydrogen gas by volume and not more than I-percent oxygen by volume. Gaseous hydrogen systems consist of items such as compressed gas containers, reactors and appurtenances, including pressure regulators, pressure relief devices, manifolds, pumps, compressors and interconnecting piping and tubing and controls.
What must be verified before using this guidance?
Gaseous Hydrogen System is defined once in this corpus, in the Special Detailed Requirements Based on Use and Occupancy chapter of the International Building Code (IBC) 2009:
An assembly of piping, devices and apparatus designed to generate, store, contain, distribute or transport a nontoxic, gaseous hydrogen-containing mixture having at least 95-percent hydrogen gas by volume and not more than I-percent oxygen by volume. Gaseous hydrogen systems consist of items such as compressed gas containers, reactors and appurtenances, including pressure regulators, pressure relief devices, manifolds, pumps, compressors and interconnecting piping and tubing and controls.
Where gaseous hydrogen system is used in the code
The term appears in 7 chapters of the 2009 I-Codes hosted here. The chapters that lean on it hardest are the ones to read next.
| Chapter | Code | Mentions |
|---|---|---|
| Motor Fuel-dispensing Facilities and Repair Garages | IFC 2009 | 9 |
| Special Detailed Requirements Based on Use and Occupancy | IBC 2009 | 6 |
| Special Fuel-burning Equipment | IRC 2009 | 4 |
| Flammable Gases and Flammable Cryogenic Fluids | IFC 2009 | 2 |
| Specific Appliances, Fireplaces and Solid Fuel-burning Equipment | IMC 2009 | 2 |
| Definitions | IBC 2009 | 1 |
| Fuel Gas | IRC 2009 | 1 |
The terms gaseous hydrogen system 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 gaseous hydrogen system covers:
- Piping — IRC 2009: Where used in this code, “piping” refers to either pipe or tubing, or both.
Gaseous Hydrogen System: 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 | |
| Re-check the requirement that uses it | Motor Fuel-dispensing Facilities and Repair Garages (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 | Special Fuel-burning Equipment (IRC 2009) | |
| Re-check the requirement that uses it | Flammable Gases and Flammable Cryogenic Fluids (IFC 2009) | |
| Confirm the dependent definition | Piping | |
| 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
- Piping: Building Code Definition
- Liquid: Building Code Definition
- Solid: Building Code Definition
- Platform: 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 gaseous hydrogen system?
The International Building Code (IBC) 2009 defines it in Special Detailed Requirements Based on Use and Occupancy as: “An assembly of piping, devices and apparatus designed to generate, store, contain, distribute or transport a nontoxic, gaseous hydrogen-containing mixture having at least 95-percent hydrogen gas by volume and not more than I-percent oxygen by volume. Gaseous hydrogen systems consist of items such as compressed gas containers, reactors and appurtenances, including pressure regulators, pressure relief devices, manifolds, pumps, compressors and interconnecting piping and tubing and controls.” 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 gaseous hydrogen system?
In this corpus the term is used across 7 chapters, led by Motor Fuel-dispensing Facilities and Repair Garages 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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