Uncertainty determination of glow-wire test for ignition of materials

The glow-wire test has been one of the basic electrotechnical material fire tests since the 1970 s. Although the test exists in a large number of versions, only one is internationally standardized as IEC 60695-2, Parts 10–13. Test results are ignition or flame persistence of a material in contact with a glow wire at a given temperature. Since the measurement is qualitative, uncertainty can only be performed on the temperature measurement itself. This article demonstrates the main verifications needed to ensure trueness and repeatability of the test and proposes a method to calculate test uncertainty. It also summarizes the results of various round-robin inter-laboratory studies and presents an example application of uncertainty determination.