Millions of bushels of grains safely flow from field to storage during harvest each year. However, one person trapped beneath the surface of the grain can stop the flow in a matter of seconds. All too often, farm workers or family members suffocate beneath the surface of grain. In Iowa, newspaper accounts show that this tragedy is repeated several times a year. The real tragedy is that many who have experienced this type of accident did not know the potential danger of handling grain.
SECONDS COUNT IN ACCIDENTSFor example, a high capacity conveyor can move 5,000 bushels of grain an hour. At that rate, a 6-foot tall person would become submerged in only 15 seconds.
Children are at an even greater risk around flowing grain. They are shorter and become submerged quicker than adults. They also do not have the physical strength to pull themselves out of grain before they become entrapped.
GRAIN TRAPS LIKE QUICKSANDEven if grain has stopped flowing, submerged objects or people are difficult to extract. Victims with tremendous upper body strength cannot pull themselves out if they are buried up to the chest. The force required to remove someone buried in grain can easily exceed 2,000 pounds, which is about the same as lifting a small car.
You can test your own strength against the force of grain. As an experiment, fill a large container such as a livestock watering trough with grain. Tie a rope to a plywood disk 2 feet in diameter, about the same diameter as a human body. Bury the disk in the grain at the bottom of the container, leaving the end of the rope above the grain surface. Then try to pull out the disk with the rope. It requires more force to pull out a 180-pound person than a wooden disk.
One devastating example of that force occurred when a man was submerged in grain up to his neck. Rescuers believed ropes would keep him from sinking farther into the grain while they emptied the rest of it from the bottom of the bin. However, the force on the rope was so great that two men could not hold the man's head above the grain. He was buried deeper and suffocated before the grain was removed.
HOW SUFFOCATION OCCURSSuffocation also occurs when the victim is no longer able to inhale air. Pressure in a grain mass can restrict a person's ability to breathe. This happens when the chest cavity and diaphragm shrinks as a person exhales, and grain quickly flows around the body, filling any areas that are voids. On the next breath, the person will have less room to expand the chest cavity and inhale air. This is similar to the way a python strangles its prey. Panic hastens the process, and as the capacity of each breath becomes smaller, the person is unable to inhale enough air to survive.
Another factor is lack of a breathable atmosphere in the grain. Typically, a person requires a specific volume of air. In a grain-handling accident, grain restricts the air flow to the area surrounding the submerged person. As the person uses oxygen and exhales carbon dioxide, the air surrounding the person is depleted of its oxygen.
HOW TO PREVENT ACCIDENTSFarm workers, however, must expose themselves to some suffocation risks. To reduce risk, follow these guidelines:
Farm workers seldom have the strength or reaction time to save themselves once they are trapped in flowing grain. However, all farm workers can recognize the dangers of flowing grain, and avoid taking risks in routine tasks.
GRAIN HARVEST SAFETY
See answers at the end of this document.
What Can You Do?Don't Drown in a Grain Wagon, Pm-1334a, and Suffocation Hazards Associated with Stored Grain, Pm-1293i, available through Extension.
For a grain wagon suffocation hazard demonstration and safety decals, contact Farm Safety 4 Just Kids at 130 East First Street, Earlham, Iowa 50072. Telephone (515) 758-282.
Answers to quiz: 1-a; 2-c; 3-d; 4-True
Publication #: Pm-1265i
This Fact Sheet is apart of a series from the Safe Farm Program, Iowa State University Extension, Ames, Iowa. Safe Farm promotes health and safety in agriculture. It is funded by the National Institute for Occupational Safety and Health, Iowa State University, and a network of groups that serve Iowa farm workers and their families. Publication date: September 1992.
Prepared by Charles V. Schwab, Extension safety specialist; Mark Hanna, Extension agricultural engineer; and Laura Miller, Extension communications, Iowa State University Extension, Ames, Iowa.
Cooperative Extension Service, Iowa State University of Science and Technology and the United States Department of Agriculture cooperating. Robert M. Anderson, Jr., director, Ames, Iowa. Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. The Iowa Cooperative Extension Service's programs and policies are consistent with pertinent federal and state laws and regulations on nondiscrimination regarding race, color, national origin, religion, sex, age and handicap.
Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More