Criteria for non-combustibility tests for class 1 laminated and decorated building materials

In Taiwan, the non-combustibility test for building materials has been changed from CNS 6532 (based on JIS 1321) to CNS 15694 (based on ISO 1182), but the non-combustibility performance is still ranked using the “old” criteria of CNS 6532. There consequently exists a need to evaluate the feasibility of existing criteria. This study analyzed the differences of the two non-combustibility test methods, i.e. CNS 6532 and CNS 15694, and discussed the criteria applying ISO 1182 in other countries. A series of experiments is conducted to evaluate whether the current criteria can adequately rank the non-combustibility performance of building materials. Ten specimens selected from laminated and decorated building materials are tested for the comparative experiment since their “reaction to fire” performance may be complicated.

Our analysis demonstrates that the thermal environment in CNS 6532 and CNS15694 are different. CNS 15694 specifies that no automatic thermostatic can be used to control the furnace during testing but CNS 6532 does not. The temperatures for CNS 6532 tests return closer to the furnace setting temperature. Accordingly, the criteria for CNS 6532 cannot be used for CNS 15694. Additionally, the experimental results show that there is no significant difference in mass loss percentage. Further, for ensuring better confirmation of fire safety, a stricter assessment is recommended. Conclusively, this study recommends that the criteria for a non-combustibility test should comply with the Japanese standard, although the duration of flame is not included.