Grain Engulfment: A Multifaceted Approach Using The Hierarchy of Controls

Grain entrapment and engulfment has impacted several grain employees in the past several months. While some of the men were able to return home to their families, several were not. The impact of these incidents has dramatically affected the families and co-workers of the victims, their communities, and the rescue workers.

The grain industry continues to raise awareness surrounding grain engulfment, yet incidents still occur at an alarming rate. How does the industry eradicate grain engulfment? The answer to this question is complex.

This article discusses a multifaceted approach using hierarchy-of-controls thinking. The hierarchy of controls is a methodology used to address hazards in the workplace. The top level of the hierarchy represents the preferred strategy. Each step down the hierarchy is a less favorable means to address the hazard. The hierarchy of grain engulfment prevention involves four levels: elimination, engineering controls, administrative controls, and personal protective/rescue equipment.

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Hierarchy Of Controls


Poor-quality grain is directly correlated to engulfment. This element often is overlooked when analyzing engulfment incidents in favor of directing attention toward employee decision making, training, and procedures. Grain in poor condition can pose a myriad of concerns including bridging, grain clinging to side walls of storage structures, steep angles of repose, and use of workers to clear or unplug sumps and reclaim systems. Eliminating or reducing engulfment hazards requires dedicated focus on monitoring and maintaining grain quality. Over the years, there have been many technological and equipment advancements that aid in monitoring and maintaining the condition of grain (grain drying, aeration, temperature cables, carbon dioxide sensors, etc.). In addition to the use of these types of systems, companies must allow enough space within each facility to move or rotate grain to maintain quality. Focusing on grain quality can reduce or eliminate the need to enter bins where the potential for engulfment exists.

Engineering Controls

There are countless engineering controls that can aid in the prevention of engulfment. Consider the use of zero-entry bin sweeps, larger reclaim sumps, and using vac systems operated from outside of the structure. These systems can eliminate the need for employees to enter structures where grain engulfment hazards exist. Engineering controls involve a significant investment. The return on investment can be justified not only with decreased exposure, but also the investment’s ability to dramatically reduce or eliminate the manpower needed to engage in activities involving exposure.

Administrative Controls

The Occupational Safety and Health Administration’s Grain Handling Standard 29CFR 1910.272 requires administrative controls, including the use of an entry permit, a trained observer, lockout/tagout of equipment that poses a hazard to employees inside the bin, as well as training. Many of the workers who recently were engulfed in grain were trained and experienced in identifying grain engulfment hazards and safe entry procedures. Administrative controls are an important element of the multi-faceted approach, but not the end all, be all.

In addition to ensuring that employees are effectively trained, consider developing a procedure-oriented permit. A procedure-oriented permit walks each entry team member through the steps involved in safe entry and encourages hazard analysis prior to and during entry. It also requires each member to sign or initial as each pre-entry step is completed. Management also should be involved in the permit approval process, not just by inserting a signature in the appropriate box, but by being present during pre-entry preparations as an active participant rather than an observer.

Personal Protective and Rescue Equipment

Personal protective and rescue equipment play an important role when entering grain storage structures. This equipment includes harnesses, lifelines, retrieval equipment, rescue tubes, etc. Employees have died in grain bins while wearing lifelines and harnesses. Personal protective equipment and retrieval systems have limitations. If not properly deployed, they can serve little purpose. Training on the purpose, setup, and use of these systems is paramount.

Each organization must be prepared for grain storage emergencies. This includes having rescue equipment available and personnel trained in rescue operations. Being prepared for rescue alone is not a prevention strategy but rather a piece of the multi-faceted approach.


To prevent grain engulfment, the industry as a whole must focus on a multifaceted approach. Effective use of the grain engulfment hierarchy of controls can ensure that the appropriate efforts and resources are evaluated and implemented. Hierarchy-of-controls thinking requires that each organization look within and evaluate their efforts to prevent these types of catastrophic events. It will take balanced involvement from merchandizing, operations, and safety personnel. Focusing a balanced effort on each of the levels of the hierarchy can assist in the prevention of grain engulfment. Simply start at the top, and work toward the bottom.

Joe Mlynek is president and safety and loss control consultant for Progressive Safety Services LLC, Gates Mills, OH; 216-403-9669; and content creation expert for Safety Made Simple, Olathe, KS.