A propane-powered box-type delivery truck has failed to negotiate a turn and has struck a utility pole. The engine compartment is on fire and the driver is unconscious and pinned inside the cab behind the steering wheel.
A propane-fed fire in the engine compartment has also ignited the left front tire of the vehicle. Fire from the burning tire is impinging on the truck's left side propane fuel tank.
The propane pressure relief device has not activated and there are visible signs that the tank has been stressed.
Propane motor fuel tanks may be installed in cars, vans, pick-up trucks, and buses. While propane-fueled vehicles have been around for decades, they are now entering the national fleet in significant numbers. They serve the same purpose as gasoline, diesel, or natural gas fueled vehicles, except the fuel is propane.
Many propane-powered motor vehicles are dual fueled and may also be equipped with gasoline tanks, which allow the operator to switch fuels based on availability and price.
Propane motor fuel tanks are manufactured in a variety of shapes to accommodate different vehicle designs. Their capacities range from 4 to 65 gallons, with most trucks and automobile tanks ranging from 35 to 65 gallons capacity. Many of these tanks are mounted in automobile trunks.
Motor fuel tanks have a maximum working pressure of 312.5 psig. NFPA 58-Liquefied Petroleum Gas Code requires that relief valves be vented to the outside of the vehicle. Discharge points on passenger cars are positioned 45 degrees from the vertical. Responders should locate the discharge points and avoid standing in this area. Relief vent piping on trucks often vents at the top of the truck.
Most valve fittings are threaded and are often limited to 1/4-inch, 3/4-inch, or 1 inch female normal pipe thread (NPT). Mobile tanks usually have a maximum of five threaded openings. Fittings must also be vented to the outside of the vehicle when the tank is installed in a confined area like a trunk or inside a camper shell. In some vans and cars, the tank installation may consist of two or three tanks manifolded together.
Fire water flows of 100 gallons per minute (gpm) are adequate for cooling motor fuel tanks of under 65 gallons capacity. Two 1-1/2 or 1-3/4 inch attack lines flowing 100 gpm or higher are recommended to cool the motor fuel tank, protect the occupant inside the vehicle, and attack and extinguish the engine compartment and tire fires.
Because the truck driver is pinned behind the steering wheel and will require extrication, an initial attack crew should place their line in service as soon as possible and rapidly attack and extinguish the tire fire on the left side of the vehicle, which is exposing the motor fuel tank to flame impingement.
Controlling the tire fire will also reduce the driver's exposure to toxic smoke generated from the burning rubber. Once the fire is brought under control, the attack crew should remain stationed on the left side of the truck and continue to cool the propane motor fuel tank.The crew should locate and close the fuel supply shut-off valve.
A second crew should attack and extinguish the engine compartment fire, then cover the rescue and emergency medical team while they rescue and treat the truck driver.
This is a top-perspective view of the incident area. Its purpose is only to get the general idea of the incident and surroundings.
In this section, we present an animated version of the incident.