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Guardian Structural Technologies

ASTM E84

Standard Test Method for Surface Burning Characteristics of Building Materials

What it measures

The Steiner tunnel test. A specimen lines the ceiling of a 25-foot tunnel and is exposed to a gas flame; the test reports a flame spread index and a smoke developed index, both scaled against red oak at 100 and cement board at 0.

Why it matters for a panel envelope

Building codes set flame spread and smoke limits for interior finishes and for foam plastics. It is the first number a code official asks for.

Guardian Shield™

EPS rigid foam flame spread index 5 to 20 and smoke developed index 95 to 300, from the EPS manufacturer's test results for the EPS specified.

Source · 3-Part Specification, 1.5 E.2 c and d · Guardian documents

Written by Data Subsystems, for Guardian Structural Technologies. Last updated .

Drafted from Guardian Structural product literature and published building-science sources. Awaiting Guardian technical review. Confirm any figure against the current product documents or ask us before you rely on it in a design.

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