The Samsung Galaxy S9 / S9+ is rated IP68, using the Ingress Protection rating system. The dust rating is 6 (highest level of protection), and the water resistance rating is 8 (water-resistant up to 5 feet for up to 30 minutes). Despite this classification, your device is not impervious to water damage in any situation.
Follow these tips carefully to prevent damage to the device:
Related Topic: Check for Physical Damage