Overview
ISO 9772:2020 - "Cellular plastics - Determination of horizontal burning characteristics of small specimens subjected to a small flame" - is a small‑scale laboratory screening method for comparing the horizontal burning behaviour of cellular plastics with apparent density less than 250 kg·m−3 (per ISO 845). It defines apparatus, specimen preparation, conditioning, test procedure, measurements and reporting for quality assurance and limited product evaluation. The method is intended for controlled laboratory comparisons and pre‑selection of materials, not for predicting full-scale fire behaviour in building or furnishing fires.
Key topics and technical requirements
- Scope and purpose: Horizontal orientation testing of small cellular plastic specimens; optional classification system for pre‑selection (Annex A).
- Material limits: Applies to cellular plastics with density < 250 kg·m−3 (ISO 845). Flexible cellular plastics and cellular rubber are covered elsewhere (ISO 3582).
- Apparatus:
- Draught‑free test enclosure (fume hood) with dark interior and extraction for safety.
- Diffusion flame burner P/PF2 as specified in ISO 10093 (barrel length (100 ± 10) mm; internal diameter (9,5 ± 0,3) mm) with a wing top opening (48 ± 1) mm × (1,3 ± 0,05) mm.
- Wire cloth support (approx. 215 mm × 75 mm) with plain weave, ~6,4 mm mesh and ~0,9 mm wire (ASTM E2016).
- Positioning equipment to hold gauze horizontal and maintain specimen 13 ± 1 mm above burner; gauze ~175 ± 25 mm above cotton indicator.
- Timing devices, measuring scale and specified cotton indicator.
- Procedure elements: Specimen preparation and conditioning, burner and specimen positioning, ignition and burning sequence, measurements of afterflame and afterglow times, damaged lengths, repeat testing rules (including provisions when specimens shrink without igniting), and calculations.
- Precision and reporting: Requirements for number of valid tests, heat‑age comparison, and test report contents are defined.
Applications and users
- Practical uses: Material selection, quality control, formulation changes, process control, and pre‑selection of cellular plastics for components in appliances and devices. Useful for identifying relative burning tendencies under a small‑flame ignition in a horizontal orientation.
- Who uses it: Materials scientists, product designers, safety engineers, quality managers, test laboratories, and standards bodies involved in plastics, packaging, transport and appliance manufacturing.
Related standards
- ISO 845 - determination of apparent density
- ISO 10093 - standard ignition sources (burner specification)
- ISO 13943 - fire safety vocabulary
- ISO 3582 - flexible cellular plastics and cellular rubber (related method)
- ASTM E2016 - wire cloth specification
- IEC 60695-11-3 - test flames (referenced for flame characteristics)
Keywords: ISO 9772:2020, cellular plastics, horizontal burning, small flame, burning characteristics, fire test, laboratory screening, ISO 845, quality assurance.