This International Standard specifies methods for determining the minimum concentration of oxygen, in admixture with nitrogen, that will support combustion of small vertical test specimens under specified test conditions. The results are defined as oxygen index values.
Methods are provided for testing materials that are self-supporting in the form of vertical bars or sheet up to 10,5 mm thick. These methods are suitable for solid, laminated or cellul?r materials characterized by an apparent density greater than 100 kg/m3. The methods may also be applicable to some cellul?r materials having an apparent density of less than 100 kg/m3. A method is provided for testing flexible sheet or film materials while supported vertically.
Oxygen index results obtained using the methods described in this International Standard can provide a sensitive measure of the burning characteristics of materials under certain controlled laboratory conditions, and hence may be useful for quality con-trol purposes. The results obtained are dependent upon the shape, orientation and isolation of the test specimen and the conditions of ignition. For particular materials or applications, it may be necessary or appropriate to specify different test conditions. Such requirements should be referred to in other standards. Results obtained from test specimens of differing thickness or by using different ignition procedures may not be comparable and no correlation with flammability behaviour under other fire conditions is implied.
Results obtained in accordance with this International Standard must not be used to describe or appraise the fire hazard presented by a particular material or shape under actual fire conditions, unless used as one element of a fire risk assessment that takes into account all of the factors pertinent to the assessment of the fire hazard of a particular application for the material.
NOTES
1 It may not be possible to apply these methods satisfactorily to materials that exhibit high levels of shrinkage when heated, e.g. highly oriented thin film.
2 For assessing the flame propagation properties of cellul?r materials of density < 100 kg/m3, attention is drawn to the method of ISO 3582 for testing horizontal burning characteristics.
SIS SS-ISO 4589:1988 history
1988SIS SS-ISO 4589:1988 Plastics — Determination of flammability by oxygen index