Scope:

This ASTM E662-14 test method is useful for research and development purposes only, not for regulatory rating reasons. Under the specified exposure conditions, the optical density of smoke that is generated by solid material specimen as well as assemblies can be determined by this test method.

Procedure

In this test procedure, an electrically heated radiant-energy source is installed within an insulated ceramic tube and positioned to produce irradiance. The specimen is mounted within the holder. Flaming and non-flaming combustion is provided to the test specimens. Smoke accumulate is measured by photometric system having vertical light path. The optical density is then calculated by using the light transmittance measurements.

Specimen size

The specimen should be conditioned at an ambient temperature of 73 ± 5 °F (23 ± 3 °C) and a relative humidity of 50 ± 5%

Data

Specific optical density, Ds, at any given time is calculated as follows:

                        D_s = G [log₁₀ (100/T)+F]

Where:

G = V/AL,

V = volume of the closed chamber, ft³ (or m³),

A = exposed area of the specimen, ft² (or m²),

L = length of the light path through the smoke, ft. (or m),

T = percent light transmittance as read from the light-sensing instrument,