Air Tools are not truly sealed units, thus water will get into the veins. However it will work safely underwater.
Here is the proper lubricating procedure to extend the life of the tool after it has been underwater for any period of time:
This procedure will replace the water in the motor with lubrication.
Also available is an Underwater Tools Cleaner (MS 9105) which can be found in the “Go-Together Items” section of each Underwater Capable tool. This cleaner too displaces the moisture in the air motor.
This procedure is best to practice at the beginning and end-of-day when Air Tools have been exposed to outdoor elements.