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Short- and Long-term Performance of Fibre-Reinforced Cement Proffi ififi le Sheets Containing Asbestos and Non-asbestos Materials 82 The Journal of the Royal Institute of Thailand Vol. 37 No. 4 Oct-Dec 2012 China were reported to still consume the large quantities of asbestos used in commercial products followed by Brazil, India, and Thailand (1) . The concern of Thai government authorities relating to the health and safety recently addresses with controlling the use of asbestos in industrial products in order to minimize the quantity of asbestos to be used. Several studies on the mechanical and durability properties for the asbestos and non-asbestos roof tiles were conducted (3, 4) . However, the controversial findings of the results reported in two studies were still in questions (5, 6) . Comments have also been addressed on the properties of tiles and the methodologies used in two studies (5) . The study was, therefore, aimed at investigating the short- and long-term performance of roof products in asbestos- and non-asbestos-reinforced cement profile sheets. The properties of tiles were also included in the study for classification of the tiles. Materials and Methods A total of 96 cement tiles which could be classified as four types; namely blue, brown, red and green tiles, were chosen for this investigation. All of the sources of these tiles were blinded. Therefore, the types of cement tiles containing asbestos or non-asbestos material were unknown during the study. The cement content for each type of tile was determined by measurement of three major cement compounds; namely calcium, silica, and alumina. A total of five specimens for each type of tile were prepared by crushing one-sixth tiles with a rock crusher. The 10-g crushing powder was dispersed with 75-ml of deionised water and then acidified with 25-ml of nitric acid. The tested sample was heated and then filtered. The major cement compositions; namely calcium, silica, and alumina, of the prepared sample were tested using the frame atomic absorption. The shape of fibre containing in each type of tile was determined by monitoring crushing powder as mentioned previously with the optical microscope using the magnification of 100x. The dimension of each tile was undertaken. The thickness of each tile was measured at six points using vernier caliper and then averaged. The corrugation height, length and width dimen- sions of each tile were also measured using a metal ruler. The bending test for the cement tiles was performed as specified within the ISO 9933 standard (7) using 1000kN universal testing machine. A total of eight specimens for each type of