Ceramic and porcelain tiles are manufactured using inert materials, pressed and fired to extreme temperatures in excess of 1200 degrees celsius. As ceramic tiles are an inert, non-combustible material, they are deemed to satisfy the requirements of the Australian Building Code.
According to the National Construction Code (Series 2015) - clause C1.10 'Fire Hazard Properties' the fire hazard properties of the floor linings, floor coverings, wall linings and ceiling linings in a Class 2 to 9 building must comply with Specification C1.10. These requirements do not apply to ceramic tiles (or the like).
For more information, please refer to page 90 of the 'NCC Building Code of Australia - Volume One'.