Noise
Grain vacs generate significant noise levels. Anyone nearby should wear hearing protection, even if they are inside the cab of a truck or tractor. The noise makes verbal communication nearly impossible, so workers need a direct line of sight to use hand signals effectively.
Dust
The grain vac's powerful suction pulls in everything in front of the hose, including dust particles separated from the grain and expelled through the exhaust chute. This creates a large, continuous cloud of dust, which can obscure visibility and pose additional hazards.
Entanglement
Many grain vacs are powered by a tractor's power take-off (PTO), which involves a four- to five-foot-long shaft spinning at 1,000 RPM (16 times per second). PTO entanglement has historically caused amputations and fatalities. Machine guards can mitigate this risk by creating a barrier around the spinning shaft, but any active PTO remains dangerous. If guards are temporarily removed or adjusted for maintenance, they must be reinstalled correctly before use. Additionally, the grain vac nozzle itself poses a danger due to its powerful suction, capable of pulling in anything in its path.
Grain entrapment
Grain vacs are designed to move large volumes of grain quickly. When the nozzle is placed into the grain, it creates a zone of rapidly moving grains. This can lead to the formation of pits or grain avalanches within seconds. The speed and volume of grain movement around the vac nozzle can make it more hazardous than an unloading auger in terms of grain entrapment.