selfignite

Self-ignite refers to the ignition of a material caused by internal heat generation rather than an external flame or spark. In safety and scientific contexts, it is often described as spontaneous combustion or self-heating that leads to ignition when the rate of heat production within a material exceeds its rate of heat loss. The concept is closely related to autoignition, but self-ignite emphasizes the buildup of heat inside a bulk substance or system rather than ignition from a defined external source.

Mechanisms of self-ignite typically involve exothermic reactions such as oxidation, decomposition, fermentation, or other chemical or biological processes that generate heat. If the environment restricts heat dissipation—due to insulation, high moisture, poor ventilation, or high surface area in powders—the accumulating heat can raise the temperature to the material’s ignition point. Risk factors include stored organic matter, such as coal, peat, hay, straw, grain, or damp compost, as well as oily or chemically reactive substances. Dust, fibers, or metal powders can also pose spontaneous combustion hazards under certain conditions.

Detection and mitigation efforts focus on preventing heat buildup and improving heat removal. This includes monitoring temperature profiles in storage or processing areas, decreasing pile sizes, enhancing ventilation, turning or aerating materials to dissipate heat, managing moisture content, and segregating incompatible or reactive substances. Fire protection plans may specify early detection thresholds and appropriate response procedures to prevent ignition from self-heat.

See also: spontaneous combustion, thermal runaway, autoignition, oxidation, fire safety.