ASTM D2863 Oxygen Index Test

ASTM D2863 Oxygen Index Test is the most economical and precise quality control test of combustible materials. Ease of use combined with a high level of precision has made this technique a primary characterization and quality control tool for the plastics and electrical cable industries and has been specified by several military and shipping groups. 

The ASTM D2863 test determines the minimum oxygen concentration required to support wax-like combustion in materials. Oxygen concentration values ​​are known as the Oxygen Index (OI) or historically the Limiting Oxygen Index (LOI). Oxygen concentration is measured using a paramagnetic oxygen analyzer and controlled by varying the relative flow of oxygen and nitrogen through a vertical glass column. The samples are supported vertically inside the glass column, and then an ignition source is placed in contact with the top edge of the sample and withdrawn.

If ignition occurs as defined differently by the standard for different types of materials, the oxygen concentration in the column decreases for the next sample. If ignition fails, the oxygen concentration is increased for the next sample. This systematic approach continues until the lowest oxygen concentration that will support the combustion of the material is determined.

According to the sample testing procedure, the test sample is placed vertically in a glass chimney and an oxygen/nitrogen environment is created by a flow from the bottom of the chimney. The upper edge of the test specimen is ignited and the oxygen concentration in the stream is reduced until the flame is no longer supported.

As the sample size, there are 6 specifications for the test sample depending on the type of material being tested. For injection molded specimens, 80 to 150 mm length, 10 mm width and 4 mm thickness are the recommended size. Results for different materials should be compared only if testing was done on samples of similar size. The Oxygen Index as a percentage is calculated from the last oxygen concentrations tested. Test results relate solely to the behavior of test samples under the conditions of this test method.

EUROLAB, together with its state-of-the-art accredited laboratories and expert team, helps you get precise and fast results within the scope of ASTM D2863 test.