The various rumors about Apple using Liquipel technology or other methods to protect its next-generation devices from water damage turned out not to be true. The iPad Air 2, iPad mini 3, iPhone 6 and iPhone 6 Plus are not waterproof. Even the Apple Watch is only water-resistant and not waterproof like some had hoped it would be.
It is unknown why Apple hasn't given its products IP67 certification protection like other popular devices, such as the Samsung Galaxy S5.
There are waterproof cases available for the iPad, but none have been released to fit the iPad Air 2 at this time.