Building Code Glossary
Normal Temperature and Pressure (NTP): Building Code Definition
How the IBC 2009, IFC 2009 define normal temperature and pressure (ntp), 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
Normal temperature and pressure (ntp) 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: “A temperature of 70°F (21°C) and a pressure of 1 atmosphere [14.7 psia (101 kPa)].” The IFC 2009 carries the same definition word for word, so the term means the same thing in each. The term is used in 8 chapters of this corpus, most often in Highly Toxic and Toxic Materials (IFC 2009), Flammable Gases and Flammable Cryogenic Fluids (IFC 2009), Scope and Administration (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, Harth founder and architectural technology specialist · Published 2026-09-07 · Updated 2026-09-07.
What does this term mean?
Normal Temperature and Pressure (NTP) — IBC 2009, Special Detailed Requirements Based on Use and Occupancy:
A temperature of 70°F (21°C) and a pressure of 1 atmosphere [14.7 psia (101 kPa)].
What must be verified before using this guidance?
Two of the I-Codes in this corpus define Normal Temperature and Pressure (NTP), in identical words.
| Code | Where it is defined | Definition |
|---|---|---|
| IBC 2009 | Special Detailed Requirements Based on Use and Occupancy | A temperature of 70°F (21°C) and a pressure of 1 atmosphere [14.7 psia (101 kPa)]. |
| IFC 2009 | Hazardous Materials-general Provisions | A temperature of 70°F (21°C) and a pressure of 1 atmosphere [14.7 psia (101 kPa)]. |
Where normal temperature and pressure (ntp) is used in the code
The term appears in 8 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 | 7 |
| Flammable Gases and Flammable Cryogenic Fluids | IFC 2009 | 3 |
| Scope and Administration | IFC 2009 | 2 |
| Definitions | IBC 2009 | 1 |
| Special Detailed Requirements Based on Use and Occupancy | IBC 2009 | 1 |
| Definitions | IFC 2009 | 1 |
| Hazardous Materials-general Provisions | IFC 2009 | 1 |
| Oxidizers, Oxidizing Gases and Oxidizing Cryogenic Fluids | IFC 2009 | 1 |
Normal Temperature and Pressure (NTP): 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 | Flammable Gases and Flammable Cryogenic Fluids (IFC 2009) | |
| Re-check the requirement that uses it | Scope and Administration (IFC 2009) | |
| Re-check the requirement that uses it | Definitions (IBC 2009) | |
| 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?
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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 normal temperature and pressure (ntp)?
The International Building Code (IBC) 2009 defines it in Special Detailed Requirements Based on Use and Occupancy as: “A temperature of 70°F (21°C) and a pressure of 1 atmosphere [14.7 psia (101 kPa)].” 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 normal temperature and pressure (ntp)?
In this corpus the term is used across 8 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.
What is the standard building code?
Building is a separate defined term. The IBC 2009 defines it as: “Any structure used or intended for supporting or sheltering any use or occupancy.” That is not the same as normal temperature and pressure (ntp), which the IBC 2009 defines as “A temperature of 70°F (21°C) and a pressure of 1 atmosphere [14.7 psia (101 kPa)].” — read both before applying either, and confirm the wording in the edition your jurisdiction has adopted.
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