PD ISO TS 16733-2-2026 PDF

Full title and description

STB PD ISO TS 16733-2-2026 — Fire safety engineering — Selection of design fire scenarios and design fires — Part 2: Design fires. This product listing is presented under the supplied title; the underlying international document is ISO/TS 16733-2:2026, Edition 2, which provides guidance for specifying design fires to be used in fire safety engineering (FSE) analyses of buildings and other structures in the built environment.

Abstract

This technical specification gives guidance on the specification of design fires used as input to engineering analyses that determine fire consequences (e.g., heat release, smoke production, temperature development, and growth/decay behaviour) for the purpose of assessing life safety, property protection and other fire-safety objectives. It explains typical representations of design fires, relevant parameters (for example heat release rate and growth/decay characteristics), and how design fires are selected and documented for use in fire safety engineering studies.

General information

• Status: Published.
• Publication date: 9 January 2026 (Edition 2, 2026-01).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.220.01 — Protection against fire in general.
• Edition / version: Edition 2 (2026).
• Number of pages: 48 pages.

(This edition replaces ISO/TS 16733-2:2021; the earlier 2021 edition was withdrawn on publication of the 2026 edition.)

Scope

Guidance for the specification and documentation of design fires to be used in fire safety engineering analyses of buildings and structures. The document covers the types of design-fire representations commonly used in FSE (including compartment fires and other enclosed-space scenarios), the parameters needed to define a design fire for analysis (for example characteristic heat release rate curves, duration, peak values and growth shapes), and recommendations on how to select fire sizes and scenarios appropriate to the fire-safety objectives of the study. The standard is intended to be used alongside methods for selection of design fire scenarios and other FSE procedures.

Key topics and requirements

• Definitions and principles for specifying design fires suitable for engineering analysis (heat release rate profiles, growth and decay phases).
• Guidance on selection of representative design-fire sizes and shapes for compartments and open spaces.
• Recommended parameters to document (e.g., peak heat release rate, t-squared growth, duration, fuel load assumptions, smoke production characteristics).
• Instructions for matching design-fire specifications to fire-safety objectives and chosen analysis methods (e.g., zone models, single-compartment methods, CFD).
• Guidance on using experimental data, published fire curves and validated correlations where appropriate.
• Requirements for clear documentation of assumptions, boundary conditions and rationale for chosen design fires to support traceability and review.

These topics reflect the technical specification’s role as practical guidance rather than prescriptive rules; users must apply professional judgement in selecting and calibrating design fires for specific projects.

Typical use and users

Primary users are fire safety engineers, consulting engineers, building designers and specialists performing fire-safety engineering analyses, model developers and researchers, and competent authorities or reviewers assessing engineered fire-safety solutions. Typical uses include: selecting and documenting design fires for evacuation and structural response studies, smoke control and egress analyses, performance-based design submissions, and verification/validation of calculation models used in FSE.

Related standards

Related and complementary ISO publications include: ISO 16733-1 (Selection of design fire scenarios — Part 1: Selection of design fire scenarios), which addresses scenario selection methodology; ISO 16730-1 (verification and validation of calculation methods) and related parts, which provide procedures for model validation; and ISO 16732-1 (fire risk assessment principles). Users typically apply ISO/TS 16733-2 in conjunction with these and other fire‑safety engineering standards and national regulations.

Keywords

design fire, design-fire specification, heat release rate, fire growth curve, fire safety engineering, FSE, compartment fire, smoke production, fire scenario selection, ISO/TS 16733-2:2026.

FAQ

Q: What is this standard?

A: ISO/TS 16733-2:2026 is a Technical Specification that provides guidance on how to define and document design fires for use in fire safety engineering analyses. The product listing here uses the provided title STB PD ISO TS 16733-2-2026 to identify that document.

Q: What does it cover?

A: It covers how to represent design fires (e.g., heat release rate profiles, growth and decay characteristics), what parameters to specify, how to align fire specifications with analysis methods and fire-safety objectives, and how to document assumptions and inputs for traceability and review.

Q: Who typically uses it?

A: Fire safety engineers and consultants, researchers, model developers, building designers involved in performance-based design, and authorities or reviewers responsible for assessing engineered fire safety solutions.

Q: Is it current or superseded?

A: ISO/TS 16733-2:2026 is the current published edition (Edition 2, published 9 January 2026). It supersedes and replaces ISO/TS 16733-2:2021 (the 2021 edition was withdrawn on publication of the 2026 edition).

Q: Is it part of a series?

A: Yes — it forms part of the ISO 16733 series on selection of design fire scenarios and design fires; Part 1 addresses selection of scenarios (ISO 16733-1) and Part 2 addresses specification of the design fires themselves. It is also intended to be used alongside other ISO FSE standards (for example ISO 16730 series on verification/validation and ISO 16732 on fire risk assessment).

Q: What are the key keywords?

A: Design fire, heat release rate, fire growth, fire scenario, fire safety engineering, compartment fire, FSE, design-fire documentation, ISO/TS 16733-2:2026.