Vehicle Fire

Vehicle fire is a field of safety engineering dealing with the ignition and spread of fires by cause in automobiles, with response to electric vehicle battery fires recently emerging as a key challeng

Vehicle Fire

Overview

Vehicle fire is a fire that can occur in all vehicles, including cars, trucks, and buses. It is triggered by various factors such as engine compartment overheating, electrical faults, fuel leakage, passenger negligence, and collision accidents. Fires spread rapidly and can cause loss of life and property, and can lead to large-scale disasters especially in enclosed spaces or tunnels. Recently, with the increasing adoption of electric vehicles, lithium-ion battery fires have drawn significant social attention.

Main Content

Causes of Vehicle Fires

  • Engine overheating: overheating due to engine oil leakage, insufficient coolant, or a clogged radiator.
  • Fuel system issues: fuel leakage and reaching the ignition point of fuel vapor.
  • Electrical faults: damaged wire insulation, short circuits, overcurrent, and poor grounding.
  • Mechanical friction: overheated brakes, bearing burnout, and transmission overheating.
  • Traffic accidents: fuel tank rupture or battery damage caused by collisions.
  • Arson and negligence: cigarette butts, leaving flammable materials, and using fire inside the vehicle.

Fire Types and Characteristics

  • Internal combustion engine vehicles: Since gasoline and diesel fuel are the main fuels, engine compartment fires account for approximately 70% of all fires. There is a risk of explosive fuel combustion during a fire.
  • Hybrid/electric vehicles: Fires caused by high-voltage (lithium-ion) batteries burn for a long time due to thermal runaway and have a high risk of re-ignition. If battery cells are damaged, chain ignition can occur.
  • Hydrogen vehicles: If the high-pressure hydrogen tank is ruptured, a flameless explosion (jet fire) can occur, which may be difficult to detect.
  • Large vehicles: Buses and trucks have a high fire load depending on their cargo, and fires often spread up to the ceiling height, making suppression difficult.

Response Methods in the Event of a Fire

1. Immediately stop in a safe location and turn off the engine.

2. Have all occupants exit and evacuate to a safe place at least 30 meters away from the vehicle.

3. Call 119 and use a fire extinguisher only when the fire is in its early stage.

4. For an engine compartment fire, do not open the hood fully; spray the extinguisher through a narrow gap.

5. For electric vehicle fires, do not spray water directly due to the risk of electric shock, and do not approach until professional firefighters arrive.

6. If the vehicle is a hydrogen vehicle or a gas leak is suspected, open all windows immediately and evacuate.

Prevention Methods

  • Regularly inspect wire insulation, connections, engine oil, and coolant condition.
  • Do not leave flammable materials in the engine compartment or inside the vehicle.
  • When tuning or modifying electrical devices, have the work done safely through certified shops.
  • Immediately after a traffic accident, always check for fuel leakage and battery damage.
  • When charging an electric vehicle, follow safety rules such as using designated chargers and checking overheating detection sensors during charging.

Recent Trends

In 2024–2025, electric vehicle fires emerged as a major issue. Cases were reported of battery fires occurring while parked or charging that burned down hundreds of vehicles, highlighting the urgent need for technologies to prevent thermal runaway in lithium-ion batteries. The National Fire Agency is introducing special firefighting equipment to suppress electric vehicle fires—such as glove-type battery fire suppression devices and suffocating extinguishing methods using large water tanks—and is expanding related training. In addition, the government is strengthening safety certification for electric vehicle batteries and pursuing measures to mandate the installation of pyro fuses that separate battery cells, materials that delay heat propagation, and early fire detection sensors. Hyundai Motor Company has improved its Battery Management System (BMS) to detect current and temperature in real time and has introduced technology that automatically disconnects the battery during an accident. Other research includes vehicle safety technologies that provide guidance announcements and lighting even in fire debris.

Related Topics

  • [[Lithium-ion battery]]
  • [[Thermal runaway]]
  • [[Electric vehicle]]
  • [[Firefighting]]
  • [[Vehicle safety]]