Iowa FACE Investigation 93IA014
October 19, 1993

Iowa Farm Worker Suffocates After Becoming Trapped in a Storage Bin Filled with an Unstable Grain Product


A 42 year-old male farmworker (victim) from Iowa died after entering a storage grain bin filled with an unstable grain product. The victim was working with his father (also the owner of the farming operation) and co-worker. At the time of the incident the three men were loading grain from the storage bin onto a grain truck. The bin measures 37 feet in diameter, 40 feet in height, and has a storage capacity of 37,000 bushels. Also, at the time of the incident the owner estimated the inside height of the grain to be 14 feet at the middle and 10 feet at the perimeter. Prior to the incident the three men were auger feeding grain from the storage bin onto a truck. Some time during the process the grain stopped feeding out. The victim then climbed to the top of the bin, secured himself with a rope and safety harness (first time in 15 years) and entered the bin in an attempt to dislodge the grain from inside. The co-worker assisted the victim at the top of grain bin. The co-worker had not been trained as a standby person and was not aware of the responsibilities of that position. Once inside the bin the victim began dislodging the grain. While dislodging the grain it became unstable and swept the victim down to the bottom of the bin. The co-worker made an attempt to rescue the victim, but was not successful. The co-worker then left the scene to call the local fire department. Firefighters and other helpers cut holes in the side of the bin, to allow grain to flow out onto the ground. After about 90 minutes the victims dead body was found at the bottom of the bin. At some point during the incident the victims father left the incident site to deliver a load of grain. The IFACE investigator concluded that in order to prevent similar occurrences, an employer should:



On August 18, 1993, a 42-year-old male farm worker died after becoming trapped in a storage bin filled with unstable grain product. On August 24, 1993, members of the Iowa Fatality Assessment and Control Evaluation staff were notified of the incident by Mary Kahler, an Occupational Nurses and Agricultural Communities staff person. On August 27, 1993, investigators from IFACE traveled to the incident site and conducted an investigation. IFACE investigators reviewed the incident with the owner, who was not present during the entire rescue operation. An IFACE investigator spoke with the co-worker about the incident via telephone communication. Other sources of information obtained were a medical examiners report and a local newspaper article.



The victim was employed by his father who owned a small farm service company. One of the services provided was the storage and delivery of grain for feed. The company had been in operation for 27 years and employed two full-time workers (owner and son). The victim had been emptying storage bins and hauling grain for the past 15 years. Part-time employees were hired annually, during peak harvesting season, to perform field work.

On the day of the incident there were three employees at the site; the victim, the victims father (owner), and a co-worker. The crew had been loading and hauling grain from the incident site throughout the morning and early afternoon. At around two o'clock in the afternoon the crew was preparing to haul another load of grain. About twenty minutes later the victim had noticed that grain had stopped feeding out of the auger. At this time the victim climbed to the top of the grain bin to investigate the problem. The co-worker followed the victim to the top of the bin to assist. When at the top of the bin the victim, for the first time, strapped on a safety harness and lifeline. At this time the father had left the incident site to deliver a load of grain. The victim entered the bin in an attempt to dislodge the grain so that it would continue to feed out. While using a pole and standing on top of the unstable product the victim began to dislodge the grain. Eventually the grain dislodged and swept the victim into the center of the grain pile. After ten minutes of unsuccessfully trying to rescue the victim, by pulling on the lifeline, the co-worker left the site to call the local fire department.

There was a considerable downpour of rain by the time firefighters and a number of other local farmers arrived at the site. Several triangular holes were cut into the sides of the bin to allow the grain to flow out. The holes allowed much of the grain to flow out slowly onto the ground. Several men entered the grain bin through a side door and attempted to uncover the victim. After about ninety minutes of trying to uncover the victim, his dead body was found near the bottom of the bin. The victim was still attached to the safety harness and lifeline, which was found to be about 4 feet to long.



The medical examiner reported the cause of death as asphyxiation and suffocation in a corn bin due to accidental fall into corn.



Recommendation #1: Employers should provide lifelines and harnesses, and ensure that workers wear them and are properly trained to use them before entering confined spaces containing unstable material.

Discussion: Necessary protective equipment, as determined by a qualified person, should be provided for workers in confined spaces. Safety belts or harnesses with lanyards are needed in all applications where dangerous environments may exist. Safety harnesses are preferred. In many cases a safety belt would not properly support an individual in an upright position to permit removal of the individual from a typical silo or bin opening. Also, workers should be trained in the proper use of safety equipment. In this case the victim had used safety equipment, it was not determined by our investigation whether or not the victim had used the proper safety equipment. This was the first time the victim had used safety equipment prior to entering a bin, given proper training the victim could possibly have saved his own life.


Recommendation #2: Employers should develop and implement safe work procedures for employees who work in, or near, confined spaces containing unstable materials.

Discussion: Employees who enter and work in a confined space or assist those working in a confined space should be trained to recognize the hazards and know the safe work practices associated with entering, working in, and exiting that area. Employees should receive training in normal and emergency entry and exit procedures, and other safe work practices associated with the specific location, type and function of the confined space and the operation to be performed. Also, employees working in the vicinity of confined spaces should be aware of the associated hazards.


Recommendation #3: Employers should develop and implement a comprehensive confined space safety program that properly trains standby persons in the use of emergency rescue procedures.

Discussion: Many fatalities in confined spaces can be directly attributed to a lack of communication with outside workers. Standby persons should be trained to:

  1. continuously monitor workers in the confined space;
  2. properly use protective equipment and rescue equipment, including lifelines;
  3. provide additional protection for the worker inside the confined space;
  4. always be stationed outside the confined space when it is occupied;
  5. maintain continual communications with the worker inside the confined space and be able to summon additional assistance when necessary; and
  6. never enter the confined space until adequate assistance is present and appropriate precautions are taken to prevent the rescuers from being disabled.


Recommendation #4: Consider retrofitting bins and similar storage facilities with mechanical leveling/raking devices, or other means to minimize the need for workers to climb and enter storage bins.

Discussion: A major hazard associated with storage vessels is entrapment in flowing grain, which can lead to suffocation of personnel. Release of bridged materials or materials adhering to sides of containers has resulted in many fatalities. Some grains are like quicksand and a person can sink rapidly. The danger is much greater if the material is being drawn from the bottom of the bin. In order to eliminate a worker from entering a grain storage bin, and exposing him/herself to the dangers, employers should retrofit bins with mechanical leveling/raking devices, or other means.



National Institute for Occupational Safety and Health, Criteria for a Recommended Standard...Working in Confined Spaces, DHHS (NIOSH) Publication Number 80-106, December 1979.

National Institute for Occupational Safety and Health, A Guide to Safety in Confined Spaces, DHHS (NIOSH) Publication Number 87-113, July 1987.


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