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Short- and Long-term Performance of Fibre-Reinforced Cement Proffi ififi le Sheets Containing Asbestos and Non-asbestos Materials 86 The Journal of the Royal Institute of Thailand Vol. 37 No. 4 Oct-Dec 2012 of ratio L expressed as 95% lower confidence limit were compared to the criterion given in the ISO 9933 (7) , three types of tiles; namely blue, brown, and red, could meet with the standard criterion. However, the green tiles failed to meet with the standard requirement due to their ratio L lower than 0.70. In addition, the standard deviation of the mean bending moment at rupture for the blue tiles was found to be the highest (see Table 2). It could be due to the fact that the failure of coating in the blue tiles caused the amount of cement unequally leaching out of the tiles. Figure 8 shows the failure of coating; such as blistering, usually observed in the blue tiles. The higher leachate of cement could possibly exhibit the mean bending moment at rupture lower than the lower leachate of cement. Heat-rain After all types of tiles were subjected to 25 cycles of heat and rain, no sign of crack cracks, delamination, and other defects on the surface of the specimens could be ob- served. It could then be concluded that all types of the tiles meet with the criterion for heat-rain test given in ISO 9933 (7) . Further test was carried out to compare the mean break- ing load per metre width for control and heat-rain-cycle sets as shown in Figure 9. It was found that the 25 cycles of heat-rain test could slightly reduce the mean breaking load per metre width of blue and brown tiles by about 14%. Whereas the results of mean breaking load per metre width for red and green tiles in the control sets were not statistically different from those corresponding sets subjected to 25 cycles of heat and rain. Conclusions 1. All types of tiles studied could be classified as category C of ISO 9933 (7) . The quantities of major compounds in the cement used for all types of the tiles were similar. Blue and brown tiles had similar shape of reinforcing fibre which was different from the shape of the fibre present in red and green tiles. 2. The bending strength results of blue and brown tiles were significantly higher than those red and green tiles. However, the bending strength of red and green tiles still met with the lowest class criterion given in ISO 9933 (7) .