I think water resistance is not standard across the rep production, even from the same factory. You can find (as I did) both water resistant and ready to swim and completely permeable watches! In my little experience I found that the most famous diver's reps (Sea Dweller, Planet Ocean, ...) probably due to "gadgets" like He-valves ... are less resistant compared to more simple pieces. The best suggestion: seal He valve appropriately, tighten properly the caseback and crown and ... check your rep resitance before washing hands.