Overview - ISO 21367:2007 (Plastics reaction to fire, vertical specimens)
ISO 21367:2007 specifies a medium-scale laboratory test method for plastics - reaction to fire - measuring heat release rate, ignitability, flame spread on vertically oriented specimens, falling droplets/particles and smoke production. The method simulates the early development stage of a fire and is intended as a screening test for intermediate/large-scale trials, factory production control, research and product development. Results are suitable for comparing reaction-to-fire performance of materials, products, composites or assemblies - with the important limitation that measured heat release rates must remain below 10 kW (tests must be stopped if exceeded).
Key topics and technical requirements
- Specimen orientation and size: vertically mounted specimens representative of the product; typical exposed area and construction specified in the standard.
- Heat release measurement: oxygen-consumption principle (oxygen depletion) in an exhaust duct to derive heat release rate (HRR).
- Smoke measurement: opacimeter for smoke opacity and calculation of smoke production rate (SPR).
- Ignition and flame spread: determination of time to ignition, sustained/transitory flaming, vertical and lateral flame spread and falling droplets/particles.
- Test apparatus components: stainless-steel hood, radiant electric heater (capable up to 75 kW/m2 irradiance; uniform over central 100×100 mm), pilot burner, specimen holder, exhaust system with flow measurement, oxygen analyser, opacimeter, heat flux meter, calibration burner and data acquisition.
- Calibration and accuracy: preliminary, operating and periodic calibrations required (includes calibration of orifice flow meters, heat flux meters and oxygen analyser).
- Specimen preparation & conditioning: backing boards, spacers and dummy specimen (calcium silicate board ~700 × 500 mm, thickness ~12 ± 3 mm, density ~800 ± 150 kg/m3) and specified conditioning atmospheres.
- Limitations & safety: warns against using the test alone to assess real fire hazard; combustible gases and hot equipment pose operator risks.
Practical applications - who uses it
- Fire test laboratories performing reaction-to-fire screening for polymeric materials and assemblies.
- Manufacturers and product developers for quality control, material selection and design iterations.
- Fire safety engineers comparing materials, informing specification decisions for interiors, components and enclosures.
- Regulatory bodies and certification schemes using medium-scale data to support larger-scale evaluation programs.
Related standards
Keywords: ISO 21367:2007, plastics reaction to fire, flame spread test, heat release rate, smoke production, vertical specimen, oxygen consumption method, medium-scale fire test.