If its anything like construction dry is worse to get out of.
And its easier to suffocate from dry content than wet.
Example: if you fall into a tank of liquid, whether its waster, oil or something else, you can tread to stay above it.
If its dry, treading motion often makes you go deeper and when you breathe out, the dry material collapses in around your chest and it gets harder and harder to breath back in because the dry material won't expand like liquid (Sand, grain, chocolate powder, or other)
It will be interesting to see if more details come out.