This paper presents the results of an experimental study into the effects of including different types (cross section, diameter, length and supplier) and dosages of polypropylene (PP) fibres on the occurrence of heat-induced concrete spalling. A new fire testing methodology named the Heat-Transfer Rate Inducing System (H-TRIS) was developed and used in an attempt to tackle some of the shortcomings of standard furnace fire testing in the practical study of heat-induced concrete spalling.