[sgentle]

In case this doesn't seem like a particularly scary situation: https://en.wikipedia.org/wiki/Grain_entrapment#Occurrence

> Half of all entrapment victims eventually become engulfed. A human body in grain takes seconds to sink, minutes to suffocate, and hours to locate and recover.

[TowerTall]

By raising your legs slowly and lying on your back, you cannot sink into quicksand. I wonder if it is the same for grain.

https://www.wikihow.com/Get-Out-of-Quicksand