Lourdes Casademont, rural agent: "The heat from a car can ignite dead vegetation and cause a forest fire."

Spain is experiencing one of the worst summers in terms of forest fires in recent years. More than twenty active fires, mostly in Castile and León, have already devastated nearly 13,000 hectares in just a few days. This gives us an idea of how easily a spark—or a simple heat source—can ignite in this extreme heat, with temperatures often exceeding 40°C and vegetation so dry that it behaves like a wick ready to burst into flames at the slightest carelessness.

Although it may seem strange, one of the most dangerous heat sources is found under internal combustion vehicles. Their catalytic converters , especially in older vehicles, reach temperatures of between 450 and 700°C, enough to ignite the finest and driest vegetation. "This happens especially with older cars, 10 or 20 years old, which have catalytic converters made of ceramic parts," explains Lourdes Casademont, senior officer in the fire prevention and investigation department of the Rural Agents corps of the Generalitat de Catalunya (Catalan Rural Agents).

Casademont clarifies that these ceramic pieces deteriorate more quickly when the car travels on rocky roads or rural tracks. "The ceramic material crumbles internally, and when the car accelerates at an intersection or when merging onto a road, it's easier for incandescent particles to become dislodged," he adds. Thus, even stopping the vehicle for a few minutes on dry grass can be enough to cause a fire, especially on days of intense heat and low humidity.

The rural agent consulted by La Vanguardia 's Moveo channel adds that when an incandescent ceramic particle comes into contact with dead plant material, it is likely to catch fire, since its autoignition temperature is about 300 degrees and no flame is required.

Furthermore, he warns that "any fine, dead material that touches the underside of the vehicle when it's at a high temperature is likely to cause a fire. Estimating the time is complicated. It depends on the ambient temperature, humidity, etc." This underscores the fact that there is no fixed rule and that even brief stops can be dangerous.

This summer, the situation is especially critical. The combination of high temperatures, dry winds, and extremely dry vegetation has caused the fires to spread rapidly, particularly affecting the communities of Castile and León, Galicia, and Andalusia. The central government has reinforced surveillance with more than 1,400 UME personnel, dozens of aircraft, and prevention units in the forests, but the risk remains high.

Spanish regulations are clear. Parking on dry vegetation in forested or rural areas can result in significant fines. Furthermore, if reckless parking causes a fire, liability may include criminal consequences, as any negligence that contributes to the start of a fire is considered a serious act.

Regarding the throwing of cigarette butts from vehicles , this practice is expressly prohibited by Article 6 of the General Traffic Regulations, which establishes that "it is prohibited to throw onto the road or in its vicinity any object that may cause fires or, in general, endanger road safety."

Since the reform of the Traffic Law, this violation has been classified as very serious and carries a fine of 500 euros and the loss of six license points . Furthermore, if throwing a cigarette butt causes a forest fire, the perpetrator can face prison sentences of up to six years.