Over the past day or so, we've seen reports of the OnePlus 5 being "unofficially water resistant". Although OnePlus didn't mention anything about ingress protection against the outside elements at the OnePlus 5's announcement, that hasn't stopped some folks from performing dunk tests with the new smartphone. Mind you, these dunk tests are no basis for calling something "water resistant", particularly when they aren't performed under the correct parameters for certification. Other smartphones that are certified for water resistance have a combination of adhesive and rubber seals...
Source: http://www.gsmarena.com/oneplus_5_has_good_chance_of_surviving_in_water_just_dont_try_it_at_home_-news-25916.php