Itsepolttoiset

Itsepolttoiset, a Finnish term, translates to "self-igniting" or "spontaneously combustible" in English. This phenomenon refers to materials that can ignite without an external source of ignition, such as a spark or flame. The process typically involves a slow oxidation reaction that generates heat. If this heat cannot dissipate into the surroundings, the material's temperature rises until it reaches its ignition point and bursts into flames.

Various substances are prone to self-ignition under specific conditions. Common examples include oily rags, especially those used with drying oils like linseed oil, which are often found in workshops and construction sites. The oxidation of the oil releases heat. If these rags are piled together, the heat can become trapped, leading to ignition. Other materials that can exhibit self-ignition include coal, certain types of hay, and some chemicals that react exothermically with air or moisture.

Factors influencing self-ignition include the material itself, its surface area, the presence of oxygen, temperature, and humidity. Proper storage and handling procedures are crucial to prevent accidental fires caused by self-ignition. This often involves storing flammable materials in well-ventilated areas, spreading out oily rags to allow for cooling, or keeping them in sealed metal containers filled with water to exclude oxygen. Understanding the conditions that lead to self-ignition is vital for fire prevention and safety.