ISO 5659-2: Plastics – Smoke generation - Part 2: Determination of optical density by a single-chamber test
ISO 5659-2 Smoke Density test – Scope
This part of ISO 5659 specifies a method of measuring smoke production from the exposed surface of specimens of essentially flat materials, composites or assemblies not exceeding 25 mm in thickness when placed in a horizontal orientation and subjected to specified levels of thermal irradiance in a closed cabinet with or without the application of a pilot flame. This method of test is applicable to all plastics and may also be used for the evaluation of other materials (e.g. rubbers, textile-coverings, painted surfaces, wood and other materials).
It is intended that the values of optical density determined by this test be taken as specific to the specimen or assembly material in the form and thickness tested, and are not to be considered inherent, fundamental, properties.
The test is intended primarily for use in research and development and in fire safety engineering of buildings, trains, ships, etc., and not as a basis for ratings for building codes or other purposes. No basis is provided for predicting the density of smoke that may be generated by the materials upon exposure to heat and flame under other (actual) exposure conditions, nor is any correlation established with measurements derived from other test methods. This test procedure excludes the effect of irritants on the eye.
It is emphasized that smoke production from a material varies according to the irradiance level to which the specimen is exposed. In making use of the results of this method, it should be borne in mind that the results are based on exposure to the specific irradiance levels of 25 kW/m2 and 50 kW/m2.
ISO 5659-2 Smoke Density test – Principle
Specimens of the product are mounted horizontally within a chamber and exposed to thermal radiation on their upper surfaces at selected levels of constant irradiance up to 50 kW/m2.
The smoke evolved is collected in the chamber, which also contains photometric equipment. The attenuation of a light beam passing through the smoke is measured. The results are reported in terms of specific optical density.
ISO 5659-2 Smoke Density test –Conditioning
> Before preparing the specimens for test, they shall be conditioned to constant mass at 23 °C ± 2 °C and (50 ± 10) % RH, where constant mass shall be considered to have been reached when two successive weighing operations, carried out at an interval of 24 h, do not differ by more than 0,1 % of the mass of the test specimen or 0,1 g, whichever is the greater (see ISO 291).
> While in the conditioning chamber, specimens shall be supported in racks so that air has access to all surfaces.
ISO 5659-2 Smoke Density test –Test Procedure
> General, The test may be carried out in the absence or in the presence of a pilot flame.
> Preparation of test chamber
> Tests with pilot flame
> Preparation of photometric system
> Loading the specimen
> Recording of light transmission
> Observations
> Termination of test
> Testing in different modes
Unless otherwise agreed, measure the percentage light transmission of four sets of three specimens for each material in accordance with the following schedule:
- Mode 1: Irradiance 25 kW/m2, no pilot flame
- Mode 2: Irradiance 25 kW/m2, pilot flame
- Mode 3: Irradiance 50 kW/m2, no pilot flame
- Mode 4: Irradiance 50 kW/m2, pilot flame