The Hidden Danger of Grain Bins
February 6, 2025
By Kriss Nelson
Instead of skyscrapers, Iowa’s rural areas feature different types of tall structures — grain bins and silos. The largest grain bin in the world is in Mason City, and it stands at 155 feet tall. While climbing grain bins is dangerous, the biggest threat to farmers is often hidden inside.
Inside the bin are piles of grain — most likely soybeans or corn harvested from the field — that can act like quicksand. Imagine climbing into a bin to remove grain that’s become crusted from spoilage. In mere seconds, you could become trapped, unable to move, with minimal hope of survival.
Grain entrapment happens when the suction of grain moving in a bin partially submerges someone, making self-rescue impossible and leading to further burial without prompt intervention.
According to Purdue University’s Agriculture Safety and Health Program’s 2023 Summary of U.S. Agricultural Confined Space-related Injuries and Fatalities, Iowa reported the most grain entrapment cases in 2023.
With Farming Comes Risk
Iowa is the No. 1 corn and No. 2 soybean-producing state. Producing billions of bushels of corn and soybeans that go toward feeding and fueling the world does not come without risk. Farming is one of the most hazardous occupations; injuries and fatalities are common due to long hours spent working around heavy machinery and in confined areas like grain bins.
“Farmers care greatly about the products they produce. They care about the end user, and they are proud of the fact they are feeding the world,” says Richard Gassman, director of Iowa’s Center for Agricultural Safety and Health (I-CASH). “Farming is a very, very dangerous industry, and they do it for the love of agriculture.”
Prioritize Grain Bin Safety
Like the construction industry's emphasis on safety training and equipment, farming demands the same, especially when working with grain bins.
According to the Great Plains Center for Public Health (GPCAH), grain engulfment has been a recognized hazard for decades. Yet both experienced and inexperienced workers continue to underestimate the deadly risks associated with the speed and force of flowing or shifting grain.
Gassman emphasizes the vital need for grain bin safety, regardless of expertise. “A farmer may think it will only take a second — just a second to go into the bin to free up crusted grain. But in just four seconds, an adult can sink knee-deep and be unable to free themselves, and within 20 seconds, they can become completely buried,” he says. “Farmers need to ensure they follow safety protocols at all times.”
Besides engulfment and entrapment, grain bin hazards include falls, dust explosions and equipment accidents.
Storing Quality Grain
Safe and reliable food supplies, as well as financial security for farmers, are ensured by maintaining the quality of stored grain on the farm; this also ensures the farmer's safety by keeping them out of full grain bins.
The most common reason victims enter bins is to address problems associated with spoiled grain. Proper grain drying is essential before farmers store their grain. Mother Nature often helps dry grain in the field; the previous harvest is a prime example. In other cases, farmers use aeration and drying systems to adjust the grain moisture to optimal storage levels.
“Farmers need to be sure they dry grain to the moisture content it needs to be for as long as it needs to be stored,” says Gassman. “Do not store it too wet. That’s when grain will clump and bridge.”
Spoiled grain forms solid masses, crusts, horizontal grain bridges and vertical grain walls that can collapse. Spoiled grain plugs augers and conveyors, necessitating entry into the structure to unclog the equipment.
Anyone who enters a storage structure containing grain or climbs onto an outdoor grain storage pile is at risk of being entrapped or engulfed in grain. Fatalities have occurred in as little as a few feet of grain.
About I-CASH
In 1990, the Iowa State Legislature identified a need for a statewide center addressing agricultural safety and health concerns. I-CASH came out of that legislative session and continues to be one of the country's only mandated, state-funded centers for agricultural safety and health.
Designated as a collaborative effort among four Iowa institutions: The University of Iowa, Iowa State University, the Iowa Department of Public Health, and the Iowa Department of Agriculture and Land Stewardship, I-CASH works to improve the health and safety of the agricultural population by developing statewide prevention and educational initiatives.
Although there have been many structural and technological changes in Iowa’s agriculture, farm-related injuries and fatalities remain higher than in other industries.
“Our goal is to be on the farm working with farmers to promote agricultural health and safety,” says Gassman.
About GPCAH
GPCAH is located in the College of Public Health at the University of Iowa. The Center was founded in 1990 and is a nationally recognized resource with an established record of developing and implementing programs of research, intervention, translation, education and outreach to prevent occupational injury and illness among agricultural workers and their families.
The Center addresses agricultural workers' health and safety needs in Iowa, Illinois, Indiana, Kansas, Minnesota, Missouri, Nebraska, Ohio and Wisconsin. These states constitute America’s most agriculturally intensive region.