ISO 11925-2:2020

Overview

ISO 11925-2:2020 - Reaction to fire tests - Ignitability of products subjected to direct impingement of flame - Part 2: Single-flame source test - defines a standardized laboratory method to determine the ignitability of products when exposed to a direct small flame. The test uses vertically oriented specimens and measures flame spread after application of a match-sized flame under zero impressed irradiance. The standard includes informative and normative annexes on precision, non‑flat products and perforated products.

Key topics and technical requirements

• Scope and intent: assesses ignitability by measuring flame spread up a vertical specimen and detecting flaming droplets/particles (via ignition of filter paper beneath the specimen).
• Specimen size and preparation: standard specimen dimensions are 250 mm × 90 mm; specimens ≤ 60 mm thickness are tested full‑thickness; thicker products are reduced to 60 mm (cut surface not exposed to flame).
• Test environment: conditioned room at (23 ± 5) °C and (50 ± 20) % relative humidity.
• Apparatus: stainless‑steel combustion chamber with controlled ventilation (airflow in chimney 0.7 ± 0.1 m/s), single‑flame burner (propane fuel, ≥95 % purity), specimen holder, timing device and means to observe reverse face.
• Flame parameters and distances: flame height check to a 20 mm flame tip; specific burner spacers and set distances for edge and surface impingement (e.g., 5 mm surface gap, burner spacer 16 mm for edge).
• Observation and results: flame spread measurement, detection of sustained flaming (>3 s = ignition), and presence of flaming droplets/particles recorded; precision information in Annex A.
• Special cases: normative Annex B covers testing of products that are not essentially flat; Annex C covers perforated end‑use products.

Applications and users

ISO 11925-2:2020 is used to:

• Evaluate ignitability of building materials, interior linings, components and transport products.
• Support product classification, regulatory compliance and fire performance specifications.
• Provide test methods for manufacturers, independent test laboratories, certification bodies, specifiers and regulatory authorities involved in fire safety, building materials testing and product development.

Typical users:

• Fire-test laboratories and quality assurance teams
• Manufacturers of construction and interior products
• Building code authorities and certification bodies
• Fire safety engineers and product compliance managers

Related standards

• EN 13238 - conditioning procedures and selection of substrates
• ISO 13943 - fire safety vocabulary
• ISO 14697 - guidance on choice of substrates for building and transport products

Keywords: ISO 11925-2:2020, reaction to fire tests, ignitability test, single-flame source test, fire safety, vertical specimen, ignition testing, building products.