The hazards of flowing grain are not obvious or well known and incidences result in fatality nearly half the time. Entrapment can occur in many situations and normally happens very quickly. Unloading operations, grain bridges and grain masses on side walls are three main causes of entrapment in grain containers. Basically, farmers or workers are exposed to this danger each time they move grain. Grain storage is an important function in agribusiness since grain prices tend to be higher later in the marketing year than at harvest. Grain storage is important to maintain flexibility in where and when grain is sold, support an efficient harvest, since grain does not have to be delivered to an off-farm location, and can provide grain gradually throughout the year for livestock feed.
We have seen an increase in incidences over the recent years with 2010 being a record breaking year for fatalities. There were nearly 10,000 commercial grain storage units (elevators, mills, ethanol factories, trucks/wagons, shipping, etc.) in 1999 and millions of farmer-owned units in the United States, alone. In 1996 there were approximately 92,000 employees working in grain elevators, 68,000 employees working in grain mills and, as of 2007, there were 2.2 million farms employing about 1,920,000 people (1). As you can see, grain engulfment dangers have the ability to impact at least two million people. Keep in mind this estimate is probably low based on illegal immigration and child/family labor which is common in farming operations.
In a study of deaths from asphyxiation and poisoning at work in the United States from 1984 through 1986 we saw a total of 42 deaths from engulfment (8). Specifically, 12 occurred in elevators or grain bins, 8 in storage bins, 5 in rail cars, 4 in sand hoppers, 2 in dump trucks and 11 in other locations (8). Remember, this only includes the working population, but highlights the variable locations where sphyxiation from engulfment can occur.
Considerations in the magnitude of this problem should be given to the vast span in age and gender that may be exposed to grain engulfment risks. In youth, agricultural work (particularly on family farms) contributed to an estimated 300 deaths and 23,500 serious, non-fatal injuries in the US in 1985 (9). These fatalities were caused by a number of exposures including loading grain, tractor rollovers, and handling large animals among others.
While exposures to asphyxiation are not the number one cause of death to youth on farms, one study highlights the risks that may pose a higher danger (10).
Please see: Table 1 - Causes of farm accidents in children