Inventory of major materials present in and around houses and their combustion emission products
Population shifts towards city centres and the expanding rural-urban fringe are likely to increase firefighting in urban and rural-urban settings. At present, extensive research on occupational exposures has been conducted at bushfires within Australia ; however the complexity and heterogeneous setting of the rural-urban interface (RUI) makes it difficult to extrapolate existing research findings to the urban and rural-urban context. There are many unknowns including exposures to additional air toxics emitted from burning materials in structures and contents, different firefighting tactics to ensure protection of people and property and more complex fire behaviour and smoke plume dispersion in urban and rural-urban settings. The combustion products are likely to be strong irritants, asphyxiants and potential carcinogens. For example, burning plastics are known to generate toxic fumes such as hydrogen cyanide and inorganic acids as well as particulates containing carcinogenic substances. Furthermore residues in ash and dust are also likely to contain harmful chemicals causing potential health hazard for people involved in clean-up after fires. Although research has been conducted on emission products from a range of materials, focus was primarily on toxicity of fire effluents in the context of structural fires. These studies do not take into account that at bushfires in the RUI, exposures will not be to individual structures but to a combination of several houses burning as well as their surroundings. Currently little is known about air toxics species emitted and exposure concentrations inhaled by fire and emergency workers during firefighting at bushfires that extend into the RUI. While at structural fires, firefighters in general wear breathing apparatus protecting them against harmful chemicals in the air, fire fighting at the RUI is often done without or with minimal respiratory protection. However, the likelihood for exposure to toxic fumes and particles, both during and after fires is high. Quantification of exposure concentrations for fire fighting in urbanised areas is required to assess exposure risks to firefighters and emergency service workers and to identify and, where possible, mitigate risks to the short- and long-term health.