Injury at Grain Elevator
KL was licensed under the United States Department of Agriculture
Federal Grain Inspection Service to take samples of grain as it
was leaving the elevator and being loaded into train cars. In addition,
it was her responsibility to inspect cars to insure that they were
dry and free of contaminants prior to grain stowage. She had been
an inspector for more than twenty years.
At about 9:00 AM, KL arrived at the A & B Farmers Cooperative
Grain Elevator and signed in at the office building. Earlier, she
had received a call that the person who was usually responsible
for inspecting the cars at the Cooperative had taken ill. More than
eight months had elapsed since KL had last been to the Cooperative.
After signing in, she walked to the cement silo-like elevator, and
ascended a flight of stairs to the control room. Located in the
control room was a machine that withdrew samples of grain as the
grain moved down a chute into the cars.
Near the sampling machine was the workstation for the A & B employee
who was responsible for loading grain into the railroad cars. It
contained a large central window and two smaller windows that provided
the loader with an excellent view of the grain cars and the grain
chute and spout. To the right of the loader's workstation was a
door which led to an exterior catwalk. The catwalk provided access
to the top of the cars. KL opened the door and walked from the catwalk
onto the first of five stationary cars that were positioned along
the siding to the grain elevator. Each grain car contained three
compartments. Inspection involved peering down into the empty compartment
to see if it was dry and clean. KL inspected all five cars and then
returned to the sampling machine in the control room.
The loader was responsible for controlling the amount of grain
that moved down the chute through the spout into each compartment.
When the car was completely loaded, it was weighed. .
The positioning of the spout over each compartment required the
coordinated efforts of the loader and the driver of a trackmobile.
The trackmobile driver moved the string of five cars to various
designated positions along the siding in accordance with instructions
given to him by the loader over hand-held radios. It required about
an hour to load the five cars, move them out of the way, and then
pull the next set of five cars into position.
KL drew grain samples and inspected, in turn, the second and third
set of five cars. Following the third set of cars, she gathered
the samples she had collected and left the grain elevator. KL stored
the bags containing the samples in her pickup truck and then went
to the office building to use the restroom.
According to the trackmobile driver, he saw KL when he went to
the office building to get a cup of coffee. He informed her that
they were starting to load the fourth set of cars. KL and the trackmobile
driver walked towards the grain elevator together. She ascended
the stairs to control room, while he went back to his trackmobile.
When KL entered to control room, she saw the loader at his workstation.
She walked across the room and through the door that led to the
catwalk She observed that the cars were slowly being pulled east
and that the spout of the grain chute was over Car No. 1's middle
(#2) compartment. The cars were not supposed to be loaded until
after she completed her inspection and had signaled the loader to
proceed. He was relatively new at the job and had started without
KL believed that she had time to inspect the four remaining cars
in the set before the first car was fully loaded and weighed. She
stepped onto the top of the car and then walked slowly west.
When she reached the grain chute, she was located approximately
10 feet in front of the loader’s workstation. Even through there
was adequate clearance, KL bent her head down as she walked under
the grain chute. She did not look to see if the loader was still
seated in front of the window. She assumed that since the chute
was over the middle compartment, he was seated at his workstation
loading grain into the compartment and was aware of her presence.
She then walked to the end of the car and stepped onto a small
platform. The next car in line was equipped with a similar platform.
She paused to determine how far out she had to step in order to
bridge the distance between the two cars.
According to KL, something hit her in the back and she fell in-between
the cars.The next thing she recalled was looking up at the bottom
of the train car, which was moving. The loader stated that he did
not see KL until she was on the platform at the end of the car.
He saw the spout of the grain chute strike her. He claimed that
he did not have sufficient time to prevent the accident. The trackmobile
driver heard screaming, and stopped. He saw that KL was under the
second car. As a consequence of the accident, KL's left leg was
amputated below the knee and her right arm was shattered just above
HF Issues: Why did this accident occur? Did the loader have
sufficient time to perceive and evaluate the situation? Could he
have radioed the trackmobile driver in time to stop car movement
so as to prevent the spout from striking KL? Did KL appreciate that
she was at risk of being struck by the spout when she stepped onto
the moving car?
HF Investigation: Apart from reading the depositions of
all the parties involved in this litigation, I met with KL at the
accident site. KL remained on the catwalk outside the control room,
while I stepped out onto the top of a car that was similar to the
one involved in the accident. I asked her several questions pertaining
to her gait and her location at various points in time. Measurements
and photographs were taken on top of the train car as well as in
the control room at the loader’s workstation. My request to have
the trackmobile driver move a set of five cars at a speed and rate
of acceleration that was typical of the operation was denied.
When KL stepped onto the moving car, she expected that the cars
would be loaded and weighed in the manner that were at other grain
elevators with which she was familiar.
When KL stepped onto the top of Car No. 1, the chute was located
over its middle compartment. Therefore, according to her expectations,
the west compartment was empty and the car had not been weighed.
KL reasoned that during the time required to perform these operations,
she would have ample time to walk west to the end of the first car,
cross over to the second car, and then begin her inspection.
However, KL’s expectancy about the sequence of car and compartment
loading was incorrect. The railroad siding at the A &B grain elevator
sloped downhill to the west. Instead of having the trackmobile pull
the loaded cars uphill, the cars, with one exception, were loaded
with the trackmobile pushing them downhill. The one exception was
Car No. 1. It was loaded first, according to the trackmobile driver,
to provide the trackmobile better traction. Then, after Car No.
1 was weighed, the trackmobile pulled all the cars up the grade
until the spout was above the west compartment of Car No. 5. From
this point on, the cars were pushed downhill as the compartments
were being loaded with grain.
• When KL stepped onto the top of Car No. 1, she believed that
its west compartment was empty and the car had not been weighed.
She was wrong. The car had been loaded and weighed before she arrived,
and the trackmobile driver was moving the cars up the hill so that
the next car to be loaded would be Car No. 5.
Did the loader have sufficient time to prevent the accident? The
speed of the cars was a critical variable in determining how much
time the loader had to perceive and respond to the situation. The
testimony of various witnesses provided the range of car speeds
from "crawling" to 2 mph. For my purposes, this range needed to
be narrowed. According to the loader, when the grain spout hit KL,
she "flew" and struck the end of the second car. In addition, on
the basis of both KL's testimony and that of the trackmobile driver,
it was known that after she was hit by the grain spout, she landed
on her back under Car No. 2. Could these results be obtained through
I modeled KL in Knowledge Revolution's Working Model, a computer
application that permits access to a virtual two-dimensional universe
in which mass, gravity, velocity, acceleration, and other physical
parameters are simulated. Each of the model's body segments was
assigned a mass based on estimates provided by other computer applications
(HumanCad and GEOBOD/MAC). KL was modeled as standing on the top
of the platform at the end of Car No. 1 facing the east platform
of Car No. 2 with a grain spout approaching her backside. There
were three experimental conditions for the impact speed of the spout:
3 mph, 2 mph, and 1 mph.
The simulation that provided the best fit with all the available
information was for an impact speed of approximately 1 mph. (At
3 mph, the model of KL was hurled onto the platform of Car No. 2.
At 2 mph, she was caught in a pinch point formed between the spout
and the end of Car No. 2.)
If the load handler was at his workstation, then the following
diagrams show the likely sequence of events that resulted in KL
being struck by the grain spout.
|If the loader was at his workstation,
in my opinion, he would have had 7 to 10 seconds to recognize the
danger and to prevent the accident. There was sufficient time for
him to radio the trackmobile driver to stop the cars. If the loader
did not see KL until just before the collision, in all likelihood
he was not looking in the direction of the grain spout during the
previous 6 seconds. (If the cars were being moved at a mean speed
of approximately 1 mph, it would have required about 3 minutes for
the trackmobile to move a distance of five cars.
During this time interval, the cars were not being loaded and therefore,
the loader did not need to attend the spout. The hand radio permitted
him to maintain contact with the trackmobile driver while leaving
In addition to analyzing the accident, recommendations were made
with the intention of reducing the likelihood of this type of accident
occurring in the furture.
Steamboat Island NW
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