Overview
ISO 5925:2025 specifies a standardized test method for measuring smoke leakage through smoke-control door and shutter assemblies and self-closing operable glazed elements. The standard covers both ambient-temperature (cold) and medium-temperature (warm) leakage tests, defining test apparatus, instrumentation, specimen preparation, procedures, observations and reporting. ISO 5925:2025 provides repeatable, laboratory-based methods to determine the leakage rate (m3/h) of smoke under defined differential pressure and temperature conditions. The standard does not set acceptable leakage limits; those are determined by regulators or project specifications.
Key topics and technical requirements
- Scope: Applies to door/shutter assemblies and self-closing glazed elements intended for smoke control. Fire resistance for glazed elements is addressed in ISO 3009.
- Test conditions:
- Ambient temperature: 20 ± 10 °C.
- Medium temperature: 200 ± 10 °C.
- Test chamber and apparatus: Typical opening around 3 m × 3 m (smaller for single-leaf doors). Apparatus leakage q_a shall not exceed 7 m3/h. Air supply/heating must replace leakage up to 55 m3/h and create a differential pressure of at least 55 Pa across the specimen.
- Instrumentation: Differential pressure measured to ±5 Pa or 10% of value; medium-temperature tests use 12 thermocouples arranged in four rows of three for temperature control and monitoring.
- Specimen and procedure: Includes requirements for number, size, construction, conditioning, pre-test analysis, set-up, air leakage measurement, observations and expression of results. Annexes provide test principle, apparatus guidance and commentary on applicability.
- Recent updates (3rd edition): added self-closing glazed elements, medium-temperature tolerance, option to run both medium-temperature tests on same specimen, moisture/evaporation controls, and procedural refinements (outlet valve, post-test operability checks).
Applications and users
ISO 5925 is used to:
- Verify smoke leakage performance of smoke-control doors, shutters and glazed elements.
- Support product development, third‑party certification and type testing in fire safety engineering.
- Provide laboratory data for smoke containment strategies used by architects, fire engineers and building authorities.
Typical users:
- Test laboratories and certification bodies
- Manufacturers of fire and smoke-control doors and glazed assemblies
- Fire safety engineers, consultants and code authorities
- Specifiers and facility managers responsible for passive fire protection
Related standards
- ISO 3009 - fire resistance tests for glazed elements (referenced for fire resistance)
- ISO 834-1 - standardized fire curves and general fire-resistance test requirements
- ISO 3008 series - related fire door standards and guidance
Keywords: ISO 5925, smoke-control door, leakage tests, ambient-temperature, medium-temperature, smoke leakage rate, fire safety, self-closing glazed elements.