Scope:

Electrical equipment such as wires, resistors, and other conductors, may overheat under certain conditions of operation or when they malfunction. Overheating can result in the ignition of the neighboring insulation material. ASTM D6194-18 test method evaluates the susceptibility of electrical insulating materials to ignition when exposed to a glowing wire. This test method determines the minimum temperature required to ignite an insulating material by the effect of a glowing heat source. The data from this test is used to categorize insulating materials based on their susceptibility to ignition.  

Test Procedure:

In ASTM D6194-18 test method, a standard test specimen is supported vertically and is exposed to electrical heating from a glow-wire set at predetermined temperatures. The temperature is raised in increments to determine the minimum temperature required to ignite the sample. 

Specimen size:

At least ten test specimens are required. They can be square or round. The square specimens should be approximately 60 × 60 mm. The round specimens should be 60 mm in diameter. Specimen thickness should be what is normally found in working conditions. Specimens with thicknesses less than 0.25 mm or greater than 6.4 mm cannot be tested with this method. 

Data:

The glow-wire ignition temperature, and the glow-wire flammability index is reported.