Overview
ISO 12472:2003 specifies a standardized test method for assessing the efficacy of intumescent seals used to seal door-to-frame clearances in timber fire-resisting door assemblies. The method is designed to be repeatable and reproducible so manufacturers, test laboratories and certification bodies can evaluate exposed intumescent sealing systems used with timber doors rated up to 1 hour fire resistance. The standard clarifies scope and limitations - notably it is not suitable for concealed intumescent seals and does not provide a measure of smoke resistance or hardware-specific protection.
Key topics and requirements
- Scope and applicability: Evaluates exposed intumescent seals in timber door assemblies (single-acting, single-leaf, latched doors) and applies results to like-for-like door sizes within the field of direct application.
- Test apparatus and rig: Defines a reproducible test rig and supporting construction to heat and mechanically load the specimen in a controlled manner (detailed apparatus and rig geometry provided in the standard).
- Specimen preparation: Requirements for seal dimensions, placement (leaf edge or frame reveal), corner jointing of hardwood lippings and conditioning of hygroscopic materials.
- Test procedure and performance criteria: Pre-test analysis, installation, furnace exposure, applied loads/movement, limits on deflection, integrity criteria and how results must be expressed and reported.
- Limitations: Not suitable for concealed seals; does not assess smoke leakage or specialized protection at hardware/ironmongery positions.
- Quality control and ageing: The method is suitable for routine quality control and detecting performance changes over time (real-time ageing), because it reduces variables and produces repeatable results.
Practical applications
- Validate and compare the fire-sealing performance of exposed intumescent seal products for timber doors.
- Support product development, manufacturing quality control and certification testing for fire doors up to 1 h rating.
- Provide defensible data for specification in building projects, replacement seals and for establishing limited product interchangeability where supported by full-scale testing.
Who uses this standard
- Intumescent seal manufacturers and R&D teams
- Fire door and timber door manufacturers
- Accredited fire test laboratories and product certification bodies
- Fire safety engineers, architects and specifiers evaluating door sealing performance
- Regulatory authorities and building control bodies assessing compliance
Related standards
- ISO 3008 - Fire resistance tests - Door and shutter assemblies
- ISO 834-1 - Fire-resistance tests - Elements of building construction
- ISO 8302 - Thermal insulation - Guarded hot plate method
- ISO 13943 - Fire safety - Vocabulary
Keywords: ISO 12472, intumescent seals, fire resistance, timber door assemblies, test method, exposed intumescent, door-to-frame sealing, fire door testing.
Open preview (PDF)Fire resistance of timber door assemblies - Method of determining the efficacy of intumescent seals