Developing an experimental database of burning characteristics of combustible informal dwelling materials based on South African informal settlement investigation

Informal settlements, which have little or no legal status and no official planning remit, such as slums, shacks and favelas, are exposed to an extensive risk of fire. Due to flammable construction materials of the dwellings, the combustibility and flammability of the materials of dwelling furnishings and the proximity and density of these settlements, fires can readily develop and spread to neighbouring dwellings. To understand the hazards related to fire development and spread, a database of material properties is required, however, the materials found within the informal settlement homes vary and are sometimes hard to define. Therefore, an accurate assessment of the common materials found in informal settlements, and their comparison to literature data, is required. This paper presents a total of 345 cone calorimeter tests used to develop a database of combustible materials found in informal settlements of the Western Cape in South Africa. Thirty-two different typical materials were collected from one South African informal settlement and heated by an electronic cone calorimeter. The critical heat flux for ignition was determined by decreasing the incident heat flux until no ignition occurrence. The materials were also heated under different heat fluxes of 30 kW/m2, 50 kW/m2 and 75 kW/m2 to simulate their burning behaviour under different fire conditions. Other important parameters were obtained including ignition time, burning time, maximum heat release rate and flame height. Different materials contribute to fire development/spread/severity in different ways and phases: for the fire development inside the shack, PU foam, carpets and clothing are most important; for fire spread between dwelling: clothing, shade netting and tyre play a key role; meanwhile for fire severity, tyre, PU foam, carpets and Masonite timber need most notice. The experimental results can provide basic data for theoretical and numerical analysis of compartment fire development and spread in informal settlements.