Safety in airsoft is very important. The most important rule is to treat an airsoft gun like a real gun. One of the first precautions to take is eyewear. Never shoot at someone who does not have eye protection. Goggles rated at at least ANSI Z87.1 work well. Paintball goggles are also common in airsoft. Don't carry an airsoft gun in public, because some are almost impossible to distinguish from real guns (you could be arrested). A good idea is to carry it in a gun case. Also, never shoot someone at point-blank range, as they are powerful enough to blind eyes/break teeth, and some, at that range, can break skin.
But don't get scared off! When airsoft players play by the rules, it is a very safe sport.