If your Blackberry has had exposure to water or moisture, you need to know whether moisture made contact with the battery or phone. This is very important in protecting and prolonging the life of your cell phone.
If your Blackberry has been exposed to any liquid, open the battery door and take out the battery, memory card and SIM card.
Once the battery has been removed, look for a rectangular white sticker on the bottom. Depending on your battery model, it may have a red stripe running through it. A BlackBerry C-S2 1000mAh standard battery, for example, has the simple white rectangular sticker on it. A C-X2 battery has a red horizontal stripe through its middle, and if it's triggered, the red or pink bleeds into the white borders.
If you are concerned about general water damage, you may also want to check your phone itself, because many carriers have multiple water damage stickers. The stickers on the phone will be square and white, and are sometimes located in the upper right hand corner beneath the battery door, or underneath the battery. If the phone has been exposed to moisture, they will turn pink or red, depending on the severity of the damage.
If you determine that your phone has taken water damage, gently dry both it and battery, and place it in a warm dry place. Do not put your battery back in, this could fry the electronics. Do not take a hair dryer to your phone, put it in an oven or a microwave, any of these things can and will fry delicate electronics.
You can also put your Blackberry in uncooked rice or silicates to draw out the moisture. The silicate material is the same found in luggage and purses. If you have it on hand, great, if not, uncooked rice is found in most homes. If you would like to get some silica, craft stores and gun shops often have it in stock. If you suspect water damage, use what you have on hand, because time is of the essence in saving your phone and its battery.
If you find that your battery has been exposed to water damage, replace it, even if your phone appears to be fine.