AS 1530.3 early fire hazard test

Fibre Reinforced Facade Encyclopedia: Testing and standards

AS 1530.3 is the Australian Standard test that measures four early fire hazard properties of a material at the same time and reports each as an index: an Ignitability Index from 0 to 20, and a Spread of Flame Index, a Heat Evolved Index and a Smoke Developed Index each from 0 to 10. A lower number is better in every case, so a result written as 0, 0, 0, 0 to 1 describes a material that did not ignite readily, did not carry flame, released little heat and produced almost no smoke.

At a glance

How the test runs

A flat specimen is mounted in a holder beside a gas fired radiant panel with a small pilot flame positioned above it. The radiant heat falling on the specimen is increased progressively while an operator records the moment sustained flaming begins. That time gives the Ignitability Index. Once the specimen is alight, the distance flame travels across its surface is read against a graduated scale, giving the Spread of Flame Index. At the same time, thermocouples in the exhaust duct record the temperature rise caused by the burning specimen, which is converted into the Heat Evolved Index, and a photometric system measures obscuration in the exhaust, which becomes the Smoke Developed Index.

Because all four are measured in one run, the four indices together describe a single behaviour rather than four independent properties. A material that resists ignition for a long time usually also returns a low spread of flame index, and a material that ignites early but then self-extinguishes may return a high ignitability index with a low flame spread index. Read the set, not one number.

Reading and quoting a result

The indices are usually written in the fixed order ignitability, spread of flame, heat evolved, smoke developed. A specification that calls for a Spread of Flame Index of not more than 0 and a Smoke Developed Index of not more than 3 is naming two of the four and leaving the others unrestricted, which is exactly what several provisions of the National Construction Code do.

The indices are dimensionless and calculated from the measured data by formulas in the standard. They cannot be converted into a group number, an EN 13501-1 class or an ASTM E84 Flame Spread Index, because each regime measures different quantities under different exposures. A product supplied into several markets holds several reports.

Where the NCC still uses AS 1530.3

For wall and ceiling linings the Code moved to the group number system under AS 5637.1, which is based on how quickly a room fire grows rather than on surface indices. AS 1530.3 was not withdrawn, and Specification 7 and the fire resistance provisions continue to use it for applications where a group number is not the right measure: linings and materials inside lift cars, materials in air handling ductwork, and certain other components.

It also survives in the external wall provisions. Several of the concessions in clause C2D10 that allow a material which is not non-combustible to be used on or attached to an external wall are conditional on AS 1530.3 indices, typically a Spread of Flame Index of not more than 0 together with a Smoke Developed Index of not more than 3. Those concessions are limited in scope and are set out on the NCC external walls page. They do not convert a combustible cladding into a compliant one; they cover thin finishes, ancillary elements and similar items.

The Code also uses the closely related AS 1530.2 flammability index, a different test, for sarking type materials. The two are frequently confused in submissions.

What the test does not tell you

• It is not a combustibility test; a material with excellent indices may still be combustible, and combustibility is settled only by AS 1530.1
• It is not a fire resistance test; no index corresponds to a duration in minutes or to a fire resistance level
• It is not a group number, and a group number cannot be derived from it
• It is a small specimen test with no cavity, no fixings and no joints, so it says nothing about the behaviour of an assembled external wall
• It does not predict performance in a full-scale facade fire, which is what AS 5113 exists to assess

Composite materials and the indices

Cementitious and gypsum based products such as glass fibre reinforced concrete and glass fibre reinforced gypsum contain no polymer matrix to burn and return very low indices, although in practice they rarely need the test because they can be assessed for non-combustibility under AS 1530.1 instead, which satisfies every fire hazard requirement in the Code.

Fibre reinforced polymer does need reaction-to-fire evidence. For linings the current route is a group number under AS 5637.1, and ShapeShell-RT holds a Group 1 classification from AWTA Product Testing. Where a project or an overseas authority specifically calls for AS 1530.3 indices, they have to be requested as a separate test on the exact laminate.

Standards and references

• AS 1530.3-1999 Methods for fire tests on building materials, components and structures, Part 3: Simultaneous determination of ignitability, flame propagation, heat release and smoke release
• AS 1530.1 (combustibility), AS 1530.2 (flammability of materials), AS 1530.4 (fire resistance of elements)
• AS 5637.1:2015 (group number for wall and ceiling linings, the successor for linings)
• NCC 2022 Volume One C2D10 and Specification 7 (fire hazard properties) (check the edition adopted in your jurisdiction)
• AS ISO 9239.1 (critical radiant flux for floor coverings), used alongside these provisions
• AS 5113:2016 (the full-scale external wall test, a different question entirely)

Related terms

• Reaction to fire versus fire resistance
• AS 5637.1 group number
• AS 1530.1 combustibility test
• Ignitability index
• Flame spread index
• Smoke developed index
• NCC external wall requirements

Questions specifiers ask

Reviewed by Richard Halvorsen, General Manager, ShapeShift Technologies. Last updated September 2026.