What is ASTM standard test method D635?

ASTM D635 is a standard test method developed by ASTM International for determining the rate of burning and/or extent and time of burning of self-supporting plastics in a horizontal position. The test method is commonly used to assess the flammability characteristics of various plastic materials.

The ASTM D635 test involves exposing a horizontal specimen of the plastic material to a controlled flame from a Bunsen burner or other suitable ignition source. The burner flame is positioned vertically above the specimen, allowing it to burn under defined conditions. During the test, the time it takes for the flame to extinguish and the extent of burning are recorded.

The test method provides guidelines for preparing the test specimens and defines specific criteria for evaluating the rate and extent of burning. It also includes provisions for conducting optional measurements, such as the heat release rate and ignition temperature.

The results of the ASTM D635 test can be used to classify the flammability characteristics of plastics and assess their suitability for various applications. It is important to note that this test method evaluates the flammability of self-supporting plastics in a horizontal position and may not be applicable to other forms or orientations of plastic materials.

To ensure reliable and consistent results, it is essential to follow the specified test conditions and procedures outlined in the ASTM D635 standard. Additionally, it is recommended to consult the relevant safety guidelines and regulations when conducting flammability testing on plastic materials.