Validating a change of technique proposed in draft ISO7176-16 ignitability testing on wheelchair materials

To investigate whether (1) the changes to the angle of application of the ignition source to the sample surface, and (2) more precise failure criteria, would result in similar outcomes (in terms of pass/fail criteria) when assessing samples in accordance with ISO CD 7176-16:2010. Time before smouldering/fire/smoke had ceased following withdrawal of the flame as well as area of burn damage were recorded. Changing the angle of application of the ignition source (45 degrees compared to 0 degrees) did not appreciably affect the ongoing smouldering/smoking of samples, but did result in increased measured burn damage for most samples. Thin structures showed more variable outcomes especially in the vertical orientation. The direction of application of a match-flame equivalent ignition source has only a moderate affect on the resulting burn damage, and that pass/fail results from the proposed revision would be consistent with the existing ISO7176-16 with the exception of the proposed burn damage criterion. It is suggested that the burn damage area be moderately increased in the draft standard to maintain consistency under the existing standard. Some benefits were identified in fixing thin coverings to underlying materials, and little value in any cleaning or laundering pre-test.