Flaming Combustion
Definition
Gas-phase oxidation of volatile pyrolysis products above the fuel surface, producing a visible flame at 800-1200°C. Produces less CO than smouldering under similar fuel and oxygen conditions.
- Process
- Gas-phase oxidation of pyrolysis products
- Location
- Above the fuel surface
- Temperature range
- 800 to 1200 degrees C
- CO output
- Lower than smouldering combustion
Common questions
Why does flaming combustion produce less carbon monoxide than smouldering?+
Flaming combustion occurs with sufficient oxygen and temperature to more completely oxidise pyrolysis gases to carbon dioxide, whereas smouldering is oxygen-limited and incomplete, favouring the partial oxidation products that include carbon monoxide.
How does this distinction matter in cause-of-death determination in a fire?+
A victim recovered with high carboxyhaemoglobin is consistent with prolonged smouldering exposure before flashover, while a scene dominated by flaming combustion from the outset with a victim showing lower carboxyhaemoglobin may point toward a different sequence of events or a non-fire cause of death.
Related terms
- Arrhenius Equation
- Mathematical expression relating reaction rate to temperature: k = A × exp(-Ea/RT). The exponential dependence explains the self-accelerating nature of combustion as...
- Auto-Ignition Temperature
- The minimum temperature at which a material ignites spontaneously without a pilot flame or spark. Relevant to the assessment of ignition scenarios...
- Carboxyhaemoglobin (COHb)
- The compound formed when carbon monoxide binds to haemoglobin at the oxygen-binding site, with an affinity 200-250 times greater than oxygen. Produces...
- Conductive Heat Transfer
- Transfer of thermal energy through a solid material by molecular vibration. Rate depends on thermal conductivity, temperature gradient, cross-sectional area, and path...
- Convective Heat Transfer
- Transfer of heat by bulk movement of a fluid (gas or liquid). In compartment fires, the buoyant hot gas plume carries most...
- Fire Tetrahedron
- The model of sustained combustion requiring four concurrent elements: fuel, oxidiser, heat, and an uninhibited radical chain reaction. Replacing the older fire...
- Flash Point
- Lowest temperature at which a liquid gives off enough vapour to form an ignitable mixture in air, but the vapour does not...
- Glowing (Smouldering) Combustion
- Surface-phase oxidation of solid char without a gas-phase flame, typically at 400-700°C. Produces large amounts of CO and can persist at lower...
- Radiative Heat Transfer
- Transfer of heat by electromagnetic waves (infrared). Scales as the fourth power of absolute temperature; at near-flashover temperatures it can simultaneously ignite...