2.10. Bin Entrapment
It takes more than 1000 lb (4.5kN) of force to remove someone buried below the surface.
The following sections cover common ways a person gets submerged or trapped:
2.10.1 Flowing Grain
• Grain flows in a funnel-shaped path when unloading. This vortex of grain behaves very much like a water
drain. Velocity increases as grain flows from the bin wall at the top of the grain mass into a small vertical col
-
umn at the center of the bin.
• Flowing grain will not support the weight of a person. Submersion happens within seconds.
Figure 1. Suffocation Hazards in Flowing Grain
2-3 SECONDS
4-5 SECONDS
22 SECONDS
AFTER THE UNLOADING
EQUIPMENT STARTS,
YOU HAVE 2-3 SECONDS
TO REACT
IN 4-5 SECONDS,
YOU ARE TRAPPED
AFTER 22 SECONDS, YOU
ARE COMPLETELY COVERED.
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