Palamisjäämistä

Palamisjäämistä, often translated as "flame retained" or "residual flame," refers to a phenomenon in combustion where a flame persists even after the primary fuel source has been extinguished or removed. This can occur in certain materials or under specific conditions where the combustion process is sustained by heat retained within the material itself or by slow-release pyrolysis gases.

This effect is most commonly observed in materials that undergo smoldering combustion, such as certain types of insulation, textiles, or porous solids. The heat generated by the initial combustion can cause the material to reach its ignition temperature internally, even if the external flame is no longer present. This internal heat then allows for continued, albeit often slower, burning fueled by the decomposition products released from the material as it heats up.

Palamisjäämistä poses a significant fire safety concern. A seemingly extinguished fire might reignite hours or even days later, leading to unexpected fire spread or rekindling. This necessitates thorough fire investigations and careful post-fire examination of materials, particularly in cases involving structural fires. Understanding the conditions that lead to palamisjäämistä is crucial for developing effective fire prevention and suppression strategies. Firefighters must ensure that smoldering materials are thoroughly cooled and extinguished to prevent re-ignition.