Smouldering (or smoldering in American spelling) is a flameless form of combustion, deriving its heat from oxidations occurring on the surface of a solid fuel. Common examples are the initiation of fires on upholstered furniture by weak heat sources (for example, a cigarette, a short-circuited wire), and the persistent combustion of biomass behind the flaming front of wildland fires. Fundamentals The fundamental difference between smouldering and flaming combustion is that smouldering occurs on… (More on Smoulder)