By: Clarke McGrath and Mark Hanna
It’s always difficult to forecast weather, but if dry field conditions persist, potential for combine and field fires this fall will continue to be a problem. There have already been dozens of significant field fires around the state, including a fire yesterday near Harlan that required five departments to contain the situation. All it takes is a single high-temperature source in the engine area, or an overheated bearing to ignite dry plant material.
During harvest periods with increased fire potential, fires cause millions of dollars in property damage in Iowa, including loss of machinery, crops, and time. Injuries to farm workers and firefighters are also an unfortunate outcome in some instances.
Modern, high-productivity combines are powerful machines; power means heat. Fire cannot start without heat and fuel. You cannot remove the heat from the engine, hydraulics, and other hard-working systems, but you can remove the fuel source by keeping your combine clean.
- Keep the machine clean, particularly around the engine and engine compartment. Use a high pressure washer or compressed air to remove caked-on oil, grease, and crop residue.
- Check coolant and oil levels daily.
- Check the pressurized oil supply line to the turbocharger for wear areas that rub and may start an oil leak.
- Frequently blow leaves, chaff and plant material from the engine area with compressed air or a portable leaf blower. Doing this one last time at night is better than in the morning when dew may make it harder to blow residues off.
- Remove plant materials wrapped on or near bearings, belts, or other moving parts.
- Examine exhaust or hot bearing surfaces. Repair leaking fuel or oil hoses, fittings or metal lines immediately.
- Inspect and clean ledges or recessed areas near fuel tanks and lines.
- Prior to fueling, wait 15 minutes to reduce the risk of a spill volatilizing and igniting.
- In case of fire, call 911 first, and then attack with fire extinguishers if it is safe to do so. Try to fight from the “black," the area already burned; fire attack from areas with combustibles (stalks for example) is much riskier.
- A fire can double in size in less than a minute. Burning embers blown downwind can spread a fire well beyond the control of your fire extinguishers in just seconds. Two ABC-type fire extinguishers are recommended: a smaller 10-pound unit in the cab and a larger 20-pound extinguisher at ground level on the combine.
- Invert and shake the extinguishers once or twice a season to ensure machine vibrations don’t compact the powder inside. A shovel to throw dirt can also help.
Create an emergency plan:
Fires may start from plant materials that have smoldered unnoticed for 15 to 30 minutes or more. The ignition source for field fires may have been the earlier passing of a truck, tractor or combine. Flames aren’t apparent until additional oxygen is supplied, perhaps by a gust of wind. Harvest crews and neighbors may want to discuss a plan for emergency tillage of a fire break should that option become advisable. Keep in mind that personal safety is more important than property loss.
Good luck and stay safe as we enter the home stretch of harvest.