Danbury Fire crews were sent to Danbury Ag Services around 3p.m. Tuesday. The man had been working on the bin when corn swept over him. Emergency workers cut holes in the bin to drain the corn, freeing the man around 7 p.m.
He was taken to Mercy Medical Center in Sioux City.
Authorities say the man was an employee at Danbury Ag Services. His name was not released.