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Accident procedures and vehicle fires

General Knowledge5 minManual section 2.20, 2.21

If you are in an accident and not badly hurt, act to prevent more damage or injury. The three basic steps at any accident are: protect the area, notify authorities, and care for the injured. You must also know what causes truck fires, how to prevent them, and how to put them out.

Protect the area

The first job at a crash scene is to keep another accident from happening at the same spot.

  • If your vehicle is in the accident, try to move it to the side of the road. This helps prevent another crash and lets traffic move.
  • If you stop to help, park away from the accident. The area right around it is needed for emergency vehicles.
  • Turn on your flashers.
  • Set out reflective triangles to warn traffic. Place them so approaching drivers spot them early enough to avoid the crash.

Notify authorities and care for the injured

  • If you have a cell phone or CB, call for help before you get out of your vehicle. If not, first protect the scene, then phone or send someone to call the police. Find out exactly where you are so you can give the location.
  • If a qualified person is already helping the injured, stay out of the way unless asked to help. Otherwise, do your best to help.
  • Do not move a badly injured person unless fire or passing traffic makes it necessary.
  • Stop heavy bleeding by pressing directly on the wound.
  • Keep the injured person warm.

Causes of vehicle fires

  • After accidents: spilled fuel, improper use of flares.
  • Tires: under-inflated tires and duals that touch.
  • Electrical system: short circuits from damaged insulation, loose connections.
  • Fuel: driver smoking, improper fueling, loose fuel connections.
  • Cargo: flammable cargo, cargo improperly sealed or loaded, poor ventilation.

Fire prevention

  • Vehicle inspection: fully inspect the electrical, fuel and exhaust systems, tires and cargo. Check that the fire extinguisher is charged.
  • En route inspection: whenever you stop on a trip, check tires, wheels and the truck body for signs of heat.
  • Follow safe procedures for fueling, using brakes, handling flares and other things that can start a fire.
  • Monitoring: check instruments and gauges often for overheating, and use the mirrors to look for smoke from tires or the vehicle.
  • Caution: use normal care with anything flammable.

Fighting a fire

Drivers who did not know what to do have made fires worse. Learn how your extinguisher works by reading its instructions before you need it.

  • Pull off the road and stop. Stop in an open area with no buildings, trees, brush, other vehicles or other burnable things nearby. Do not pull into a service station!
  • Notify emergency services of the problem and your location.
  • Keep the fire from spreading before you try to put it out.
  • Engine fire: turn off the engine as soon as you can. Do not open the hood if you can avoid it. Shoot the extinguisher through the louvers, radiator, or from under the vehicle.
  • Cargo fire in a van or box trailer: leave the doors closed, above all if you carry hazardous materials. Opening the doors feeds oxygen to the fire and can make it burn very fast.
  • Stay as far away from the fire as you can while using the extinguisher.
  • Point the extinguisher at the base or source of the fire, not into the flames above it.
  • Stand upwind, and let the wind carry the extinguisher agent to the fire.
  • Keep going until whatever was burning is cooled. No smoke or flame does not mean the fire cannot restart.
  • If you do not know which agent is right, above all with hazardous materials, leave it to firefighters.

Classes of fire and the right extinguisher

  • Class A: wood, paper, ordinary combustibles. Put out by cooling and quenching with water or dry chemicals.
  • Class B: gasoline, oil, grease and other greasy liquids. Put out by smothering, cooling or heat shielding with carbon dioxide or dry chemicals.
  • Class C: electrical equipment fires. Use an agent that does not conduct electricity, such as carbon dioxide or dry chemical. Never use water.
  • Class D: burning combustible metals. Use special extinguishing powders.
  • A B:C extinguisher works on electrical fires and burning liquids. An A:B:C extinguisher also works on burning wood, paper and cloth.
  • Water is fine on wood, paper or cloth. Never use water on an electrical fire (shock) or a gasoline fire (it spreads the flames).
  • A burning tire must be cooled; it can take a lot of water.
  • Extinguisher types by class: regular dry chemical — B or C; multi-purpose dry chemical — A, B, C or D; Purple K dry chemical — B or C; KCL dry chemical — B, C; dry powder special compound — D; carbon dioxide (dry) — B, C; halogenated agent (gas) — B, C; water and water with anti-freeze — A; loaded-stream water — A, B; foam — B, and some A.

References and scope

The topic reference is listed below. Sources support verification; the lesson itself is here. The current content needs technical and language review before public launch.

Manual reference: 2.20, 2.21

Official CDL handbook · Utah ↗StatesOur editorial approach

Put it into practice

Educational questions with explanations. The answer review also works without the interactive quiz.

Preparing your questions…

Review questions with answers

  1. What are the three basic steps at any accident scene?
    1. Protect the area, notify authorities, care for the injured
    2. Move the vehicles, call your boss, take photos
    3. Call insurance, exchange numbers, leave
    4. Care for the injured, clean up, drive away
    Show answer
    Protect the area, notify authorities, care for the injured

    The basic steps are to protect the area, notify authorities and care for the injured.

  2. You stop to help at an accident you were not involved in. Where should you park?
    1. As close as possible to the wreck
    2. In the travel lane behind it
    3. Away from the accident
    4. Right in front of the wrecked vehicle
    Show answer
    Away from the accident

    Park away from the accident; the area around it is needed for emergency vehicles.

  3. The first thing to do at an accident scene is to:
    1. Call your dispatcher
    2. Keep another accident from happening in the same spot
    3. Take pictures of the damage
    4. Move all injured people
    Show answer
    Keep another accident from happening in the same spot

    First protect the area so another crash does not happen at the same place.

  4. You have a CB radio and are involved in an accident. When should you call for help?
    1. Only after setting out triangles
    2. After you check the cargo
    3. After the police arrive
    4. Before you get out of your vehicle
    Show answer
    Before you get out of your vehicle

    With a cell phone or CB, call for help before you get out. Without one, protect the scene first, then call or send someone.

  5. How should you stop heavy bleeding from a wound?
    1. Apply direct pressure to the wound
    2. Pour water on it
    3. Raise the person's head
    4. Give the person something to drink
    Show answer
    Apply direct pressure to the wound

    Stop heavy bleeding by applying direct pressure to the wound.

  6. You should move a severely injured person only when:
    1. They ask you to
    2. You need to take photos
    3. Fire or passing traffic makes it necessary
    4. The police are late
    Show answer
    Fire or passing traffic makes it necessary

    Leave a badly hurt person where they are unless fire or passing traffic makes moving them necessary.

  7. A qualified person is already helping the injured at a crash. You should:
    1. Take over the first aid
    2. Stay out of the way unless asked to help
    3. Move the injured to your truck
    4. Leave the scene right away
    Show answer
    Stay out of the way unless asked to help

    If a qualified person is helping, stay out of the way unless asked to assist.

  8. Which is a common cause of tire fires?
    1. Over-inflated tires
    2. Cold weather
    3. New tread
    4. Under-inflated tires and duals that touch
    Show answer
    Under-inflated tires and duals that touch

    Under-inflated tires and dual tires that touch can heat up and catch fire.

  9. Short circuits from damaged insulation and loose connections are fire causes in the:
    1. Electrical system
    2. Fuel system
    3. Cargo
    4. Tires
    Show answer
    Electrical system

    Electrical fires come from short circuits due to damaged insulation and loose connections.

  10. During en route inspections, to help prevent fires you should check:
    1. The radio and lights
    2. The paperwork
    3. Tires, wheels and truck body for signs of heat
    4. The fuel price
    Show answer
    Tires, wheels and truck body for signs of heat

    Whenever you stop during a trip, check tires, wheels and the truck body for signs of heat.

  11. Your truck catches fire on the highway. Where should you stop?
    1. At the nearest gas station so they can help
    2. In an open area away from buildings, trees, brush and other vehicles
    3. Under a bridge for shade
    4. Next to a building with a water hose
    Show answer
    In an open area away from buildings, trees, brush and other vehicles

    Park in an open area away from anything that can burn. Do not pull into a service station.

  12. For an engine fire, you should:
    1. Open the hood wide to reach the fire
    2. Keep the engine running to cool it
    3. Pour water on it
    4. Turn off the engine and avoid opening the hood; spray through louvers, radiator or from underneath
    Show answer
    Turn off the engine and avoid opening the hood; spray through louvers, radiator or from underneath

    Turn off the engine. Do not open the hood if you can avoid it; shoot the agent through louvers, the radiator or from under the vehicle.

  13. There is a cargo fire inside your van trailer. You should:
    1. Keep the doors shut
    2. Open the doors to let the smoke out
    3. Open the doors and spray water inside
    4. Unload the cargo quickly
    Show answer
    Keep the doors shut

    Keep the doors shut, especially with hazmat. Opening them supplies oxygen and can make the fire burn very fast.

  14. When using a fire extinguisher, you should aim at:
    1. The top of the flames
    2. The smoke
    3. The source or base of the fire
    4. The air above the fire
    Show answer
    The source or base of the fire

    Point the extinguisher at the base or source of the fire, not into the flames above it.

  15. When using an extinguisher, you should get as close to the fire as possible.
    1. True
    2. False
    Show answer
    False

    False. Stay as far away from the fire as possible, stand upwind, and let the wind carry the agent to the fire.

  16. A B:C fire extinguisher is designed for:
    1. Burning wood, paper and cloth only
    2. Burning metals
    3. Tire fires only
    4. Electrical fires and burning liquids
    Show answer
    Electrical fires and burning liquids

    B:C works on electrical fires and burning liquids. A:B:C also works on wood, paper and cloth.

  17. Why should you NOT use water on a gasoline fire?
    1. It will spread the flames
    2. It causes electric shock
    3. It freezes the fuel
    4. It is too slow
    Show answer
    It will spread the flames

    Water spreads a gasoline fire. On an electrical fire, water can cause shock.

  18. What does it take to put out a burning tire?
    1. A small CO2 blast
    2. Covering it with a tarp
    3. Cooling it, which may take a lot of water
    4. Letting the air out
    Show answer
    Cooling it, which may take a lot of water

    A burning tire must be cooled, and lots of water may be needed.

  19. The smoke and flames are gone. What is true?
    1. The fire is surely out
    2. The fire can still restart; keep going until what was burning is cooled
    3. You may drive away now
    4. You should open the doors to check
    Show answer
    The fire can still restart; keep going until what was burning is cooled

    No smoke or flame does not prove the fire is out; it can flare up again. Keep going until whatever burned has cooled.

  20. You are not sure which extinguisher to use on a hazardous materials fire. You should:
    1. Use water
    2. Open the cargo doors
    3. Drive to a fire station
    4. Wait for firefighters
    Show answer
    Wait for firefighters

    If you are not sure what to use, especially on a hazmat fire, wait for firefighters.

  21. Class C fires involve:
    1. Electrical equipment
    2. Wood and paper
    3. Gasoline and grease
    4. Combustible metals
    Show answer
    Electrical equipment

    Class C is electrical equipment fires: use non-conducting agents like CO2 or dry chemical, never water.

  22. Where should you stand when fighting a fire?
    1. Downwind
    2. Directly over it
    3. Upwind
    4. Inside the cab
    Show answer
    Upwind

    Position yourself upwind and let the wind carry the extinguisher to the fire.

  23. As part of fire prevention during your vehicle inspection, you should check that:
    1. The radio works
    2. The fire extinguisher is charged
    3. The mud flaps are clean
    4. The cab is locked
    Show answer
    The fire extinguisher is charged

    Inspect electrical, fuel and exhaust systems, tires and cargo, and make sure the extinguisher is charged.