Overview
ISO 12468-1:2013 - External exposure of roofs to fire: Part 1: Test method defines a standardized laboratory method to assess how roof systems behave when exposed to external fires. The test simulates burning brands (embers) combined with wind and, for the most severe exposure, additional radiant heat. It measures external fire spread, fire spread within the roof, fire penetration, and the production of flaming droplets or debris.
Keywords: ISO 12468-1:2013, external exposure of roofs to fire, roof fire testing, burning brands, fire penetration
Key technical topics and requirements
- Exposure levels: Three fire exposure levels are defined:
- Level A - large burning brand from adjacent building; considers wind and additional radiant heat.
- Level B - medium burning brand from neighbourhood fire; considers wind only.
- Level C - small burning brand transported by wind from remote fire; considers wind only.
- Measured outcomes:
- External fire spread across the exposed surface
- Fire spread within the roof layers
- Fire penetration (openings, sustained underside flaming, or flaming debris)
- Production of flaming droplets or debris that continue to burn for ≥5 s
- Specimen requirements:
- Representative roof sections required; two specimens per exposure level.
- Standard specimen size: 1 200 mm ± 10 mm (width) × 2 000 mm ± 10 mm (length) for each test pitch (larger specimens allowed if necessary).
- Pitch selection rules: <5° test at 0°; 5°–20° test at 15°; >20° test at 30°.
- Test apparatus and controls: Includes burning-brand sources, wind generation, optional radiant panel, calibration elements, specimen holder and timing devices. The standard specifies conditioning, edge protection, ignition procedure, timing and post-test examination.
- Safety: The document highlights the hazards of fire testing (toxic smoke, operational risks) and requires risk assessment, written safety instructions, and trained personnel.
Practical applications and users
ISO 12468-1:2013 is used to:
- Certify and classify roof coverings and roof systems for resistance to ember attack and external fires.
- Inform design decisions for fire-safe roofing materials and assemblies.
- Support regulatory compliance, product standards, and building code references.
- Provide test data for manufacturers, fire test laboratories, fire safety engineers, building inspectors, specifiers, insurers and risk assessors.
Keywords: roof fire resistance testing, ember attack, roof system classification
Related standards
- ISO 12468-2: Classification of roofs (companion document)
- ISO 12468-3: Commentary (guidance)
- ISO 13943: Fire safety - Vocabulary (referenced terminology)
This standard provides a reproducible, laboratory-based method to evaluate how roofs respond to external fire exposures and produces test evidence used in product development, certification and regulatory assessment.