ISO 6021:2024

Overview

ISO 6021:2024 - Firebrand generator specifies rules and requirements for the construction and operation of firebrand generators. Intended as an internationally harmonized solution, the standard describes a stand‑alone, reproducible device (reduced‑scale and full‑scale concepts) that produces controlled, continuous firebrand showers for laboratory and experimental testing. It addresses the need to replicate firebrand transport and ignition phenomena observed in large outdoor fires, including wildland‑urban interface (WUI) and urban fire scenarios.

Key topics and technical requirements

• Scope and terminology: Defines key terms (firebrand, spot fire, wildland fire, WUI) aligning with ISO 13943 vocabulary.
• Device description: The ISO Standard Firebrand Generator comprises a stainless‑steel main body and a continuous feeding component with alternating gates, a conveyor, mesh support, blower and handheld propane burner.
• Principles of operation: Continuous feeding of wood pieces produces a distribution of firebrands; blower speed controls glowing versus flaming firebrand showers. The generator can be adapted for wind‑tunnel or wind‑facility testing.
• Operation parameters (examples provided in standard): conveyor speed, feed spacing and feed rate; sample fuel dimensions and mesh support; blower power/velocity guidance; burner/flame configuration. (The standard contains specific measured values and guidance for reproducible settings.)
• Reproducibility and validation: Both reduced‑scale and full‑scale designs have been reproduced by independent laboratories; the number and mass flux of firebrands are to be determined according to feed conditions.
• Alternative methods: Annex A reviews other firebrand generation approaches and situates the standard generator within test practice.

Applications and users

• Practical uses:
  • Laboratory simulation of firebrand showers for material and assembly testing (roofing, decking, walls, mulch, vegetation).
  • Research into firebrand transport, accumulation and ignition of structures in WUI and large outdoor fires.
  • Development and validation of fire‑resistant construction systems and mitigation measures.
• Who should use ISO 6021:2024:
  • Fire safety researchers and universities
  • Test laboratories and certification bodies
  • Fire protection engineers and product manufacturers (roofing, cladding, decking)
  • Emergency planners, regulators and authorities having jurisdiction concerned with wildfire resilience

Related standards

• ISO 13943 (Fire safety - Vocabulary) - normative reference used for terminology.
• Other referenced ISO technical reports and guidance on WUI and outdoor fire behavior (as cited within the document).

Keywords: ISO 6021, firebrand generator, firebrand showers, fire testing, WUI, wildland‑urban interface, fire safety standards, firebrand generation.