Respiration

Respiration is an enchantment applied to helmets that extends underwater breathing time.

Respiration can be obtained from enchanting tables, drops from mobs that have spawned in a raid,‌[Bedrock Edition only] books obtained by fishing, monster room chests, librarian villagers (or if the "Villager Trade Rebalance" experimental datapack is enabled, a swamp librarian), and non-village structure loot.

Respiration grants an oxygen bonus of +1 per enchantment level, which equates to +15 seconds per level in addition to the default time of 15 seconds. It also grants a chance of not taking drowning damage each second by level / (level + 1). The maximum level that can be obtained without commands is level 3, resulting in a total time of 60 seconds underwater (including the base time without enchantments) before drowning begins, and a 75% chance to not take drowning damage each second. Wearing a turtle shell extends this time by an additional 10 seconds. Respiration can be applied to non-helmet items by use of commands.