Overview
ISO/TR 15658:2009 - Fire resistance tests - Guidelines for the design and conduct of non-furnace-based large-scale tests and simulation - provides guidance for designing, conducting and reporting “natural” or non-furnace-based large-scale fire resistance tests. It covers duration- or time-based experiments intended to evaluate the behaviour of structural frames, rooms or suites of rooms under fully developed fire conditions (large tests in which the flame width is 1 m or more). The Technical Report is informative and intended to improve the quality, comparability and validity of non-standard fire testing and simulation data.
Key topics and technical requirements
- Scope and applicability
- Applies to non-furnace-based, large-scale, duration/time-based “natural” fire tests (not reaction-to-fire material tests).
- Defines “large” as flame width ≥ 1 m.
- Test design requirements
- Define clear test objectives before designing the assembly.
- Consider scale effects and thermal inertia when reducing test size; quantify any scaling assumptions.
- Address ambient environmental conditions (air movement, temperature, humidity) and justify chosen conditions relative to in‑use scenarios.
- Assembly and specimen considerations
- Guidance on size, construction, selection and preparation of test assemblies and specimens.
- Heating, ventilation and exhaust
- Selection and justification of heating conditions (natural fuels, burners), ventilation and exhaust arrangements, and any controlled decay conditions.
- Test conditions and measurements
- Specify thermal, pressure and mechanical conditions; timing; required output measurements; and data recording/storage protocols.
- Test procedure and safety
- Procedures for ignition, monitoring, observations, termination/extinguishing and post-test analysis.
- Mandatory hazard assessment, written safety instructions and training for personnel.
- Reporting
- Requirements for stating objectives, characterizing experimental conditions, expressing results, describing specimens and defining validity/field of application of conclusions.
Applications and users
- Primary users
- Fire testing laboratories, fire engineers, researchers, regulatory authorities and building safety assessors.
- Practical applications
- Generating realistic large-scale fire data for structural fire performance where furnace tests are impractical.
- Supplying validation data for fire modelling and computational fire dynamics (CFD).
- Informing design decisions for structural frames, compartmentation and ventilation strategies under fully developed fires.
- Improving reproducibility and comparability of bespoke or ad-hoc large-scale fire experiments.
Related standards
- ISO 13943 - Fire safety - Vocabulary (referenced for terms and definitions).
- Prepared under ISO/TC 92 (Fire Safety), Subcommittee SC 2 (Fire Containment).
Keywords: ISO/TR 15658:2009, fire resistance tests, non-furnace-based large-scale tests, natural fire tests, fire testing guidelines, fire engineering, fire modelling, test design, test reporting.