sealPurdue News

June 4, 1999

Farmers should use extra caution with gasoline

WEST LAFAYETTE, Ind. -- Farmers who are accustomed to using diesel fuel should remind themselves of the increased danger when using gasoline, says Purdue University farm safety expert Doug Kingman.

Most farmers use diesel fuel to operate tractors, trucks and other farm equipment. But gasoline still is needed for older farm machinery and lawn equipment.

"Diesel fuel is not only more economical to use than gasoline, it is also safer to handle," Kingman said. "But farmers who use diesel fuel daily can become indifferent to the hazards associated with other types of fuel, such as gasoline or liquid propane gas."

Already this spring, a White County, Ind., farmer was killed while loading gasoline into a fuel tank that ignited. Kingman said that far more fires on farms are caused by gasoline than diesel fuel, even though diesel is more commonly used.

One gallon of gasoline can vaporize and fill a 250-gallon fuel tank with explosive vapor; that single gallon of gasoline has the explosive energy of 83 sticks of dynamite. "Gasoline vapors are three to four times heavier than air and move about fuel tanks and unventilated areas like a fluid," Kingman said. "On a warm day, an uncapped gasoline storage tank may release several gallons of fuel.

"These lingering vapors can easily be ignited by items such as a nearby welder, water heater, or even by sparks from something such as a weed trimmer."

Diesel fuel is much less volatile than gasoline. The flash point of gasoline (the temperature at which it becomes explosive) is minus 45 degrees; diesel fuel has a flash point of 110 degrees. Gasoline will vaporize at 0 degrees, while diesel vaporizes at 100 degrees.

"A farmer who routinely hauls diesel fuel in large, portable tanks or small containers in the back of a truck may unknowingly begin to disregard safety procedures when handling gasoline," Kingman warned. "Unsafe practices such as smoking or using power tools are much less forgiving when they are done around gasoline."

Kingman offered these additional safety precautions:

  • Power tools, electrical equipment and electric pumps that can be used in the presence of diesel fuel can become dangerous near gasoline because they are potential ignition sources.

  • In a truck with a plastic bed liner, remove gas cans and set them on the ground before refilling. The plastic bed liners can build up static electricity and ignite the gasoline.

  • When filling a gasoline tank, place the fuel nozzle against the fuel tank inlet. This contact will prevent a buildup of static electricity in the fuel hose.

To extinguish a fuel fire, use an ABC-type dry chemical fire extinguisher. "Trying to extinguish a gas or diesel fire with water can lead to disaster," Kingman said. "The water converts to steam, which only spreads the fire.

"Every tractor, truck or vehicle that transports fuel should have at least one five-pound ABC-type fire extinguisher on board."

For additional information about on-farm hazards, contact the Purdue University Agricultural Safety and Health Program at (765) 494-5013.

Source: Doug Kingman, (765) 496-1356;

Writer: Steve Tally, (765) 494-9809;

Purdue News Service: (765) 494-2096;

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