Fire behaviour of sandwich panels

Publisher Summary One of the most recent definitions for a sandwich panel is the one used in the proposed European product standard (draft) prEN 14509. This product standard defines a sandwich panel as a building product consisting of two metal faces positioned on either side of a core that is a rigid thermally insulating material, which is firmly bonded to both faces so that the three components act compositely when under load. In many cases, sandwich panels can be self-supporting, which means that the panels are capable of supporting, by virtue of their materials and shape, their own load and in the case of panels fixed to spaced structural supports all applied loadings, and transmitting these loadings to the supports. The number of fires involving sandwich panels with a combustible core has increased substantially over the last few years and they are considered to be a growing fire problem in the fire safety of buildings especially in food factories and in cold storage rooms, warehouses, etc. The sandwich panels are built up as composite construction products, i.e., they consist of two metal sheets with inner core insulation. This core insulation can be either combustible or non-combustible. The metal can cause a delay in ignition but still transfer heat to the core. Once on fire, such panels with a combustible core are known to be difficult to extinguish since the combustible material is behind a metal facing. The reaction of a product to fire involves characteristics such as ignition, flame spread, heat release rate, smoke and gas production, occurrence of burning droplets and parts. Simulating end-use conditions in a realistic way is very important when evaluating the burning behavior of sandwich panels. Based on the results of a series of tests conducted both in free-standing test rooms, this chapter discusses a number of conclusions drawn by ISO 9705 room test configuration and the SBI test protocol.