University of Illinois Extension

List of Hazardous Equipment

Power Takeoff (PTO) Hazard Demonstration

In the PTO hazard demonstration a full-size shortened PTO shaft is used, along with a full length 3 inch tubular integral-journal shield. These are mounted on a flat metal base (see images). A used tractor PTO stub shaft is mounted onto one end of the frame. A sliding collar coupler is used to attach the PTO shaft to the tractor PTO stub shaft. The universal joint at the opposite end of the sliding collar is rigidly mounted using a set screw. A 0.5 inch hex head bolt head is used on the tractor PTO stubshaft end to drive the PTO shaft using a 3/8 inch cordless drill and nut driver. The shaft, shield, universal joints, and sliding collar can be purchased at a local agricultural supply store.

One intent of the demonstration is to explain the functioning of the PTO shaft. The shortened size-3 foot overall, allows easy transport for use in situations where an actual piece of equipment is unavailable or impractical. The size also allows the audience to actually handle the PTO shaft and take it apart. This feature has been effectively used with EMT and fire/rescue squads when discussing entrapment and extrication. News clips of recent incidents can lead to discussions of audience personal involvement in similar situations. Slides, or 8 x 10 inch laminated pictures illustrating common uses of PTO shafts in farming or other agricultural situations, allows for interaction with the audience.

Another intent of the PTO hazard demonstration is to show the speed at which a PTO shaft turns. A 7 foot length of sash cord is tied to the sliding collar universal joint. The length is selected according to a 540 rpm shaft rotating at full speed and having a 3" diameter shield. In one second the rotating shaft makes 9 revolutions, and travels 7.1 feet. Thus, if an article of clothing were to become entangled on the shield, the rotating shaft would attempt to wrap that length around itself. The cordless drill will not rotate the shaft at full speed, it will typically take something over 2 seconds (depending on battery charge) to wrap the 7 foot string. This provides a good reference to situations in which the shaft does not rotate at full speed but is still hazardous.

A very effective interactive activity to use in conjunction with the above involves a lapsed time vs distance traveled chart, and a commercially available reaction timer. After the speed demonstration of the PTO shaft, the reaction timer can be used by individuals in the audience. Readings are obtained and then compared to the readings with the hundredths of seconds listed on the chart and the distance traveled in that length of time. The comparison illustrates there is little time to do anything and the question "What could you do anyway?" can be asked.

A last intent is to show the need for shaft shielding. By removing one end of the shaft using the sliding collar, the actual shaft itself can be viewed. The rectangular solid and tube shafts can be pointed out to and related to slides or pictures illustrating actual unprotected shafts in use. Discussion can follow about unprotected shaft edges and the increased hazard they represent.

The PTO hazard demonstration has been used with junior high students, high school students, farm families, EMT and fire/rescue squad training. Targeting information to the specific audience is necessary, but the demonstration has its applications in each.

Lapsed time vs distance traveled chart: Technically, the measurement is the length of time it takes a person to move the hand from the current position to the pad to shut off the timer. Reaction time would be shorter as it is usually defined as " the time between the onset of a stimulus and the making of the response to that stimulus" (Kantowitz & Roediger, 1984) so it would not include the time to move the hand to shut off the timer. For the purposes of the demonstration, however, the practical situation necessarily reaches from when the situation is first comprehended to the time action is taken. This reinforces the fact that in most situations are not seen until too late. Thanks to Dr. Kathyrn Campbell for the advice and reference. (Hubbard Scientific, P.O. Box 760, Chippewa Falls, WI 54729) Kantowitz, B.H. & Roediger, H.L. (1984). Experimental psychology: Understanding psychological research (2nd Ed.). St. Paul, MN: West Publishing.

Farm Family Insurance Companies, PO Box 656, Albany, NY 12201-0656

Grain Auger Hazard Demonstration

The main intent of the grain auger hazard demonstration is to present how a grain auger actually works. The demonstration uses a commercially available 4 inch auger kit containing tube, auger, end pieces, and a grate-type grain intake guard. The auger and tube are shortened to a length of 3 feet. Rectangular intake and outlet spouts are added. These are then mounted on a flat metal base (see images). A rectangular opening is cut into one side of the auger to facilitate viewing how flighting through rotation moves the grain. This opening also conveys why a grain auger is considered a dangerous piece of equipment. The rectangular opening is covered with plexiglass tubing that has been cut in half lengthwise. A inch hex head bolt head is used at the intake end to drive the auger using a 3/8 inch cordless drill. The grate-type grain intake guard is carried as a separate piece.

For EMT and fire/rescue squads, understanding the mechanism is necessary to prepare for patient injuries and to properly extricate an entrapped individual. It is therefore tremendously advantageous to use an actual piece of equipment in a shortened form, since it allows manipulation by hand and ease of transport. By showing grain movement within the auger, the recommendation not to reverse the auger in an attempt to extricate an entrapped individual can also be explained.

The grate-type grain intake guard can be compared with slides, or 8 x 10 inch laminated pictures, of grain augers with little or no guarding. The presence of the intake guard also allows emphasis to be made to the fact that guarding has limitations, and show how it can be dangerous when an adult hand is inserted through the guard openings. This can lead to a discussion on how such an act could affect youth and children.

The grain auger demonstration has been used with junior high students, high school students, farm families, and EMT and fire/rescue squad training. Targeting information to the specific audience is necessary, but the demonstration can be adapted to each.

Grain Bin Hazard Demonstration

One intent of the grain bin hazard demonstration is to simulate the action of grain being removed from a grain bin via a center auger. The demonstration uses a 2 foot deep, 12 inch radius semi-circle of flat metal with plexiglass across the face diameter of the semi-circle (see images). Flat metal is welded to one end of the semi-circle to form a flat bottom, and an opening is cut to allow for removal of grain by sliding a metal plate covering. An additional opening with metal plate covering is placed on each side surface. The 18 inch base allows for placing a 5 gallon bucket underneath to catch grain being removed. Spouts on each side opening direct grain into containers placed beneath each. The size depicted in the images will hold at least 25 gallons of corn.

The size of the demonstration depicts realistically the flow of grain within the bin, as it is being removed through the lower opening. When a doll is placed at the edge of the grain as it is being removed, it gets pulled down towards the center. The actual time for this action to take place in a full size bin is dependent on the size of the auger and the speed of operation. A poster from Iowa State University Extension Service, Can You Win a Tug-of-War with Grain, is used to illustrate a specific circumstance.

The demonstration can also be used to simulate the hazards of vertical grain engulfment and bridged grain. In the former, grain is let out of one of the side openings, and the doll is placed near the base of the column of grain. Movement of grain on the top causes a cascading action to take place. To show bridged grain (horizontal crusted grain surface), a thin piece of wood or a piece of heavy cardboard is placed beneath the surface of the grain. As the grain is being removed, a pocket forms under the material. These illustrations can initiate discussions on the causes of these phenomena, and the appropriate actions to be taken. The side openings allow depiction of grain action if the rescue technique of cutting openings in the bin side is used. A poster from Iowa State University Extension Service, How much strength do you need to rescue someone in grain, is used to illustrate a specific circumstance. This poster is effective with farmers to demonstrate the downward force of grain, the effect of that downward force in the engulfment process, and the ineffectiveness of common responses in flowing grain incidents. The poster is also useful with EMT and fire/rescue squads to indicate potential patient conditions resulting from the downward force, the manner in which to approach an engulfed individual, and the need for multiple personnel in extrication incidents. Whenever possible an interactive activity such as burying a one foot circle of wood with a rope in the center of a water tank of corn, will allow participants to experience the difficulty of pulling the circle of wood out.

A third intent of the grain bin hazard demonstration is to present strategies for extricating engulfed or submerged individuals. After removing grain and allowing the doll to become engulfed or submerged, discussions of pertinent recommendations for extrication should be introduced.

The grain bin hazard demonstration has been used demonstrate grain bin hazards to high school students, farmers and their families, and EMT and fire/rescue squads. While this particular demonstration can be used with youth, a more applicable demonstration uses a small gravity flow grain wagon with plastic in one side to depict hazards and explain precautions.

Vertical Grain Engulfment

Occasionally victims have been buried beneath a collapsed wall of free-standing grain. Grain in good condition will pile at an angle of 30 degrees with the floor but spoiled or caked grain can stand almost vertical. As grain is removed from the base of a caked mass, the potential for avalanche and engulfment is very real. Reports of entrapment in this manner generally have come from large grain handling facilities rather than farm operations. However, this risk is feasible on many farms with large bins.

Bridged Grain

A few reported entrapments and suffocation have taken place when a victim entered a bin in which the surface of the grain had become caked due to spoilage. In this situation the surface appears solid, but it is in fact, a thin layer of crusted grain concealing a void created when the grain underneath was removed. The victim breaks through the crust and is quickly covered by an avalanche of grain collapsing into the cavity. Survival from this type of entrapment is reduced in many instances because the unloading equipment is left running and draws the victim even deeper into the grain mass.

Farm Hazard Scene

4x8 diorama that depicts several hazards commonly found on farms.  Stores in two metal cabinets that are on wheels. Requires truck or large SUV to transport.

Small Grain Wagons

Small tabletop gravity flow wagon with clear plastic on one side. Can be used to demonstrate grain flow hazards to children and youth.