Fire ratings for flooring explained

In Australia, the National Construction Code (NCC) 2022 Volume One defines the fire hazard property requirements for flooring in Class 2 to 9 buildings. These buildings encompass various types, including offices, retail spaces, and healthcare facilities. The fire rating of flooring is determined by the values from the AS ISO 9239.1-2003.

Specification 7 (formerly NCC 2019 C1.10 Fire hazard properties) outlines fire rating criteria for flooring, including:

Critical Radiant Flux (CRF)
Smoke Development Rate
Group Number for only when the floor covering is continued more than 150mm up a wall

These requirements ensure flooring materials meet the necessary fire safety standards for different building applications. Always check test reports to verify compliance with Specification 7.

The fire test method for floorings

The Australian standard AS ISO 9239.1-2003, is the standard test method used to assess the fire performance of flooring materials.

It measures:

Critical Radiant Flux (CRF): Also referred to as Critical Heat Flux (CHF in kW/m²), this determines the minimum heat required to sustain flame spread.

Smoke Development Rate: Measured in %.min, this evaluates the amount of smoke generated during combustion.

Test results from AS ISO 9239.1 help determine whether the flooring meets National Construction Code (NCC) fire safety requirements.

A general rule of thumb:

If the Critical Radiant Flux (CRF) > 4.5 kW/m² and the Smoke Development Rate < 750%.min, the flooring complies in Class 2 to 9 buildings with or without sprinklers.

The ultimate guide to Australian fire safety requirements for flooring

Understanding National Construction Code (NCC) fire safety requirements for flooring can be complex, but we’ve made it simple.

Our visual and easy-to-follow guide breaks down fire rating requirements by area, helping you quickly identify the right flooring solutions for fire safety compliance.

Clear, visual format for easy reference
Breakdown by area to simplify compliance
The go-to resource for architects, designers, and builders

Download your free guide.

Understanding fire test reports

Technical terms in test reports can differ from those used in the National Construction Code (NCC) and Building Code of Australia (BCA). We've created a comparison table that translates key testing terms into NCC specifications to make interpretation easier.

Flooring fire test terminology comparison:

Test Method (AS 9239.1) | NCC/BCA Equivalent

CHF Value | Critical radiant flux (CHF)
Smoke Value | Smoke development rate
Mean | Final average result

How to meet fire standards with AS ISO 9239.1 testing

To comply with National Construction Code (NCC) fire safety requirements for flooring, manufacturers and suppliers must ensure their products are tested under AS ISO 9239.1-2003, which assesses a flooring material’s reaction to fire.

This standard is identical to ISO 9239-1 and specifies the burning behaviour of flooring when exposed to a radiant heat source.

Architecture & Design Team

Forbo Flooring

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