If you’re a farmer, you’ve probably worked on and around grain bins, those huge round steel buildings seen on almost every farm.
There was a time when falling into one of those was a death sentence. The pressure of the grain pushes on you; and, if someone tries to rescue you, they may fall in, too.
The grain is pushing against you, trying to get into every nook and cranny, even your nose. When that happens, a person automatically opens his mouth; and, that fills with grain, too. You will not be able to breathe.