Main Characteristics: The aim for passive fire protection systems is typically demonstrated in fire testing the ability to maintain the item or the side to be protected at or below either 140ºC (for walls, floors and electrical circuits required to have a fire-resistance rating) or ca. 550ºC, which is considered the critical temperature for structural steel, above which it is in jeopardy of losing its strength, leading to collapse. This is based, in most countries, on the basic test standards for walls and floors, such as BS 476: Part 22: 1987, BS EN 1364-1: 1999 & BS EN 1364-2: 1999 or ASTM E119. Smaller components, such as fire dampers, fire doors, etc. , follow suit in the main intentions of the basic standard for walls and floors. Fire testing involves live fire exposures upwards of 1100ºC, depending on the fire-resistance rating and duration one is after. More items than just fire exposures are typically required to be tested to ensure the survivability of the system under realistic conditions. To accomplish these aims, many different types of materials are employed in the design and construction of systems. For instance, common endothermic building materials include calcium silicate board,concrete and gypsum wallboard. During fire testing of concrete floor slabs, water can be seen to boil out of a slab. Gypsum wall board typically loses all its strength during a fire. The use of endothermic materials is established and proven to be sound engineering practice. The chemically bound water inside these materials sublimes. During this process, the unexposed side cannot exceed the boiling point of water