Most of the Russian commercial airports follow IATA rules . You will find international standards used worldwide observed

The exception I personally noticed is that security can be slightly more strict in the republics

- More rigerous ID checking i, i.e Kazan, Ufa and Grozny
- A lot more nudescopes, with the operator nearby. ( and yes the operator just saw you totally naked) . At least in EU/US the operator is hidden in another room.

The water thing is a standard rule. If you take too much you may have to ditch it at security, that's all.