In less than a minute you or someone you care about can suffocate in a grain bin.
“When you are trapped by grain and exhale to breathe, the grain flows into the space created by the movement of your chest, placing pressure on your chest and reducing the space that your lungs have to expand during your next inhalation. Each time you exhale a breath, the space around your chest decreases ….” – Pennsylvania eXtension article describing what happens to an individual trapped by grain.
After extended rains last fall, corn and soybeans may have been stored at a higher moisture content than usual. This moisture, along with the resulting molds, can lead to grain and particularly soybeans going out of condition and clogging or crusting in the bin. It may be tempting to enter the bin to break the crust and facilitate grain movement, but it is unsafe and can be life-threatening.
On Saturday afternoon, February 9, a Nebraska City farmer and another man were loading out their third truck of soybeans from a farm near Unadilla. When the flow of beans to the auger stopped, the farmer entered the grain bin to loosen the bridged beans. Unfortunately, he became entrapped in the grain and when he didn’t respond to calls from outside the bin, rescue workers from three towns were called. They cut into the bin perimeter to empty the grain, but unfortunately, it was too late to save the farmer’s life.
Keeping grain in good condition is one of the first and most important steps in grain bin safety, advises Aaron Yoder, an associate professor at the University of Nebraska Medical Center. Storing wet grain, as was the case for many this year, can lead to molds and clogs. Also, with fluctuating cold and then warm temperatures, grain freezes and thaws. As the grain cools, condensation builds up and as it freezes, the ice can create bridges or clogs that will interfere with grain flow from the bin. Yoder encouraged farmers and farm workers to never enter a bin without a safety plan, including always having someone outside the bin to monitor their safety.
Yoder describes four scenarios that can lead to grain entrapment:
1 – Flowing Grain
An auger is used to move grain from the bottom center to the outer edge of a grain bin, and from there into a vehicle or alternative storage area. As the grain flows, it forms a funnel, with the wide mouth of the funnel at the top and a smaller opening at the bottom, as shown in the diagram above. If you are in the bin when the grain is being unloaded, you can quickly become engulfed in grain. Depending on the size of the auger, you can be trapped in grain up to your waist within 10 seconds and completely submerged within 25 seconds. Once you are submerged in grain, it can take over 1,000 lb. of force to free your body.
2 – Grain Bridge Collapse
A grain bridge forms when grain in poor condition exists throughout a bin. Cavities or pockets of loose grain can form under the crusted level when the auger begins to unload grain from the bin. Grain bridges are not stable, and if you are standing on top of a grain bridge when it collapses, you can quickly become entrapped in the grain. Once you fall through the grain bridge and are trapped, it may be difficult to locate you because the grain will flow rapidly into the area around you.
The proper way to break up or remove a grain bridge is to use a long pole inserted through an access hole from outside the grain bin.
3 – Grain Wall Avalanche
Moldy or frozen grain can cling to the side of a grain bin, as shown in the diagram above. A grain avalanche can occur when you are breaking up crusted grain from within a bin and the grain wall is higher than you. The grain wall can collapse, creating an avalanche that can quickly engulf you, causing injury or death.
If you must enter a bin, use a body harness and a safety line that is securely tied off. Work above the vertical grain wall, staying above its highest point.
4 – Use of a Grain Vacuum
Grain vacuums are being used with higher frequency as a means of moving grain rapidly from older bins with smaller unloading augers, bins in remote locations without augers, and bins that have mechanical problems. Powered by a tractor power take-off, electricity, or an external motor, these vacuums have the capacity to move several thousand bushels of grain an hour. Typically, an operator uses the vacuum inside the bin, moving the nozzle in a sweeping motion. During the last few years, several operators have been killed when using the equipment in this manner. If the operator drops or releases the nozzle, it can quickly become buried in grain. As a result, the operator may try to lift the nozzle while the vacuum is running. This can cause the grain to be sucked out from under the operator, burying him or her in seconds.
Don’t take shortcuts when working in enclosed spaces with grain. Take time to stay safe. Whenever possible use inspection holes and grain bin level markers rather than entering the bin. If you have to enter the bin:
- Always wear a body harness that is securely attached to the outside of the grain bin. (See above video.)
- Never work alone. Tell others that you’ll be entering the bin and always have a second person outside who can provide assistance.
- Establish a system of hand signals to communicate over the noise of operations.
- Never enter a bin while the auger is running. Lock off and tag the auger so someone doesn’t turn it on while you’re inside.
- Keep safety tools handy. Attach a long rod to the bin for prodding grain from a distance.
Resource: Entrapment Risk Due to Flowing Grain