Fire Prevention and Safety Considerations During Harvest

By Joshua Michel

All it takes to start a fire is just a spark from an engine, an overheated bearing on a combine, or a hot exhaust manifold where some dirt and dry plant material have gathered. Dry plant residue, dusty conditions, low humidity levels and strong winds are a recipe for combine and field fires. During harvest periods with increased fire potential, fires cause millions of dollars in property damage in Iowa, including loss of machinery, crops, and time. Supply chain issues and limited availability of parts may only further plague down equipment. Injuries to farm workers and firefighters are also an unfortunate outcome in some instances.

Modern, high-productivity combines are powerful machines; power means heat. A fire cannot start without heat and fuel. You may not be able to remove the heat from the engine, hydraulics, and other hard-working systems, but you can remove the fuel source by keeping your combine and other equipment clean.

The potential risk for combine and field fires is always higher during harvest, but it doesn’t have to be. Taking a few minutes and following these steps and management tips could significantly help mitigate these risks.

Prevention tips:

• 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.
• Frequently check air filters, ensuring that they stay clean; either by blowing them out or replacing them. This will help the engine run cooler and more efficient.
• Check coolant and oil levels daily. Pay close attention to engine and hydrostatic pump parts as well.
• Check the pressurized oil supply line to the turbocharger for wear areas that rub and may start an oil leak.
• At the end of each day blow leaves, chaff and plant material from the engine area with either compressed air or a portable leaf blower. Waiting until the next morning to do this may be more difficult because of the dew.
• Remove plant materials wrapped on or near any bearings, belts, chains, or other moving parts.
• Examine the exhaust or any 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 refueling, turn the combine off and wait 15 minutes to reduce the risk of a spill volatilizing and igniting.
• Research from South Dakota State University suggests that if we have dry conditions and start experiencing wind speeds close to 30 mph and above, fires may be inevitable. During these periods producers should consider delaying harvest until evening hours when winds decrease or wait for precipitation. Higher humidity levels may also reduce the potential for field fires to spread.

Management tips:

• In case of fire, turn off the engine, get away from the machine, and call 911. Then attack with fire extinguishers if it is safe to do so. Try to fight from the “black," the area already burned. Attacking a fire from areas with combustibles (e.g. dry corn stalks) is much riskier. Always stay upwind of a fire to minimize the risk of exposure from smoke, heat, and possible flames.
• A fire can double in size in less than a minute. Burning embers blown downwind can easily spread a fire well beyond the control of your fire extinguishers in just seconds. So be aware of possible additional fires.
• It is recommended to have two ABC-rated fire extinguishers on hand: a smaller 10-pound unit in the cab and a larger 20-pound extinguisher at ground level on the combine. Keeping an extra fire extinguisher on other pieces of machinery or trucks that are out in the field is also a good idea.
• Invert the fire extinguisher once or twice during the season to ensure that machine vibrations don’t compact the powder inside.
• Keeping a shovel on the combine to throw dirt on a fire can also help.
• Create a list with the 911 addresses for each of your field locations prior to harvest and have them easily accessible to family members and farm employees. Many fire departments are equipped with GPS equipment or mobile apps to assist in directing them to incidents. When a fire is called in with a 911 address, dispatch can more readily identify the incident location and relay this information to the fire department. This can save precious time as some fields may be in remote locations.

Create an emergency plan:

Fires can start from plant materials that may have been smoldering unnoticed for 30 minutes or more. The ignition source for field fires may have been the earlier passing of a truck, tractor, or combine. Flames may not be 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 firebreak should that option become advisable. The goal of creating a firebreak with a tillage pass; is to stop an out-of-control fire from spreading. It creates an area that won’t fuel the fire, so the fire will eventually burn itself out.

Keep in mind that personal safety is far more important than property loss. Attempting to fight a fire should only happen after calling 911 and determining that it’s safe to do so. Fire prevention is possible; it just requires some regular maintenance and keeping equipment clean.