Which energies are primarily involved in a vehicle crash that can cause secondary fire?

• A. Thermal energy and sound energy.
• B. Fuel energy and kinetic energy.
• C. Potential energy and chemical energy.
• D. Electrical energy and magnetic energy.

Answer: (B)

Two energy forms drive the possibility of a secondary fire after a crash: the vehicle’s kinetic energy and the chemical energy stored in the fuel. During a collision, rapid deceleration converts kinetic energy into deformation work and heat, which can rupture fuel lines or the tank and create hot spots or sparks. If fuel is released and vapors are present, that chemical energy can ignite when an ignition source—such as hot metal, electrical arcing, or a nearby flame—interacts with the vapors. The other energy types (thermal and sound, or potential energy, or electrical/magnetic energy) aren’t the primary drivers of ignition in this scenario, so the combination of released fuel and the energy from the crash itself is what most increases the risk of a secondary fire.