Fire prevention tips during harvest from ISU Extension

 The following is reprinted with permission from Iowa State University Extension.

Joshua Michel, Field Agronomist in northeastern Iowa, Iowa State University Extension

Harvest season has started across most of the state and according to the latest U.S. Drought Monitor, the majority of the state is abnormally dry with pockets of moderate drought in northeastern and southwestern Minnesota. These abnormally dry conditions could enhance the potential for combine and field fires this fall. Low relative humidity levels and high winds will further increase the risk of fires. Fires cause millions of dollars in property damage, including loss of machinery, crops, and time. Unfortunately, injuries to farm workers and firefighters may also occur.

Modern combines are powerful machines, which means they can produce excessive amounts of heat. All it takes to start a fire is a single high-temperature source in the engine area or an overheated bearing to ignite some dry plant material. While it’s impossible to remove the heat from the engine, hydraulics, and other hard-working systems, you can minimize the risk of fires by taking a few minutes and following these fire prevention steps and safety tips.

Prevention steps

• 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 efficiently.
• 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.

Safety 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. Additional information on creating a firebreak using tillage can be found in this ICM Article from 2021.

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.