Performance of Intumescent Fire Protection Coatings in Non-Standard Heating Scenarios

Introduction

In recent years Intumescent coatings have become an essential means of passive fire protection in large scale structural buildings. Intumescent coatings increase the fire resistance time of structural elements exposed to high temperatures, by swelling and forming a layer of carbonaceous char, which acts as a thermal barrier, to effectively insulate and thus protect structural elements against any temperature increases during a fire (Han, 2010). The fire ratings of structural elements, protected with Intumescent coatings, are currently established:

  • in large scale furnace tests in accordance with BS 476 in the United Kingdom and Ireland (and ASTM E119 in North America).  
  • using bench-scale cone calorimeter experiments in accordance with ISO 5660. (Bailey, 2009)

Currently the effects, of the typical change in heat flux experienced during a fire, on steel elements, protected using intumescent coatings, is estimated by simulating the time-temperature growth of a real fire using the standard ISO 834 curve. Current testing procedures have not considered how Intumescent coatings react under non-standard fire scenarios i.e. varying/ more realistic rates of heating.

It is proposed to test steel plate specimens, coated with water-based intumescent coating, under non-standard heat fluxes/temperatures using  a Cone Calorimeter and a Flame Propagation Apparatus (FPA). The purpose being to establish the efficiency  of Intumescent coatings in various fire scenarios such as travelling fires, Eurocode smouldering fire and the standard time-temperature ISO 834 curve. Since Intumescent coatings have a life safety function it is vital that more realistic testing procedures are carried out to establish whether current manufacturers guarantees  are accurate.









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This website was created, by Connie Leydon and Patricia Lehane, in partial satisfaction of the requirements for the degree of Master of Engineering, in Civil Engineering (Leydon) / Civil & Environmental Engineering (Lehane), at the University of Edinburgh, U.K. ©