Fire Protection of Structural Steel Using Intumescent Coating
While it is not combustible, steel can be affected by fire. Once steel is heated above 200°C the properties of the steel in relation to its yield stress and it’s modulus of elasticity begin to change. As the temperature gets higher the steels ability to continue to carry the same load as it is designed for significantly reduces. The temperature at which the steel loses its ability to carry its design load is known as the critical temperature and in a fire an unprotected piece of steel can reach this quite quickly. The purpose of passive steel protection systems such as board, paints and sprays is to insulate the steel and increase the time it takes for the steel to reach that critical temperature. The thickness of material required will be based on the Fire resistance Level (FRL) it needs to meet in accordance with the NCC, along with the size of the steel and the critical temperature that the steel has been designed too. In simple terms the larger the piece of steel is, the less protection will be required. All Promat products and systems have been tested at nationally accredited laboratories around the world to a variety of standards, e.g. AS 1530: Part 4, AS4100, EN13381-4, EN13381-8, BS 476: Part 21, DIN 4102 and ASTM E119.