Workplace Health and Safety Queensland recently issued a safety alert highlighting the risk of collapse of transportable (relocatable) silos, commonly used on farms.
The alert was issued following an incident in May 2020 in which a five-metre high grain silo collapsed while a farmer was underneath it attempting to position a grain auger and release the slide gate (knife plate) on the discharge cone.
It appears the support framework buckled on one side of the silo, causing the body of the silo to topple sideways onto the ground.
The impact with the ground caused the skin of the silo to tear away from the silo base, spilling grain onto the ground.
The farmer was trapped for some time until he could be removed.
In addition to being severely injured, there was also a risk of the farmer being engulfed (i.e. suffocation risk) in the grain as it emptied from the ruptured silo.
The cause of the failure is currently being investigated but so far it has not been determined why the support framework failed.
Support frames on silos can fail for one or more of the following factors:
Transportable silos are generally designed to be lightweight to allow easy movement. This characteristic means that this type of silo can be blown over when it is empty and not anchored to the ground or support pad.
The lightweight design of the silo means that damage from being blown over is certain to occur.
The Workplace Health and Safety Queensland safety alert said silos must be set up in accordance with the manufacturer’s instructions. Ensure silos: