It says not to grind over steaming pots on the label of the pepper grinder. Is this so you don't get burned or for some other reason?
There are two possibilities I can see:
- The steam can wet the pepper in the mill and cause it to cake in the grinding mechanism
- There's an over-protective lawyer worried someone will scald themselves and blame the grinder company.
Which of the two is your guess. Personally I use my grinder over steaming pots all the time and I've never had any problems, but YMMV.
If the grinder has a steel mechanism, rust could be the concern.
I think all hand-held grinders have this warning of not grinding over steaming or boiling-hot contents.
The grinding action could splash the hot contents and scald your hands. If hot oil is involved - temporary or long-term blindness. You might accidentally slip your hands into the hot pot.
No legal dept of a manufacturer would want that to happen to their customers. To them users are idiots tending to sue.
You should never season over steaming pots of anything. The moisture ruins the seasoning.
Just pour season in the palm of your hand then dump in. (Always keep hands washed when cooking)