Good wisdom from the good folks at Airsoftgunhelp.com. Safety should always be first when you handle any firearm- airsoft or otherwise.
Airsoft Safety

Many people are concerned that the realism of airsoft guns makes them dangerous. Parents need to be aware that giving an airsoft gun to irresponsible children can put their child in danger. In certain countries where real firearms are illegal the police and others may understand that children are playing with fake guns. In the United States, however, airsoft guns are regularly mistaken for real guns. Just as you would not brandish a real firearm in public, the same is true with airsoft guns. Airsoft guns are not cap guns or squirt guns. Be aware that if your child brings an airsoft gun to school or any other public place they may be arrested or, at worst, shot by a police officer.
If you are a parent and are reading this, thank you for taking responsibility and being pro-active in learning about airsoft guns. To learn more about airsoft gun safety please read on.
Not only do airsoft guns appear to be real, they also shoot plastic pellets. Many of the more expensive models such as
AEGs are fully automatic. The speed at which airsoft bb's come out of airsoft guns is much slower than the speed that bb's are shot out of a traditional bb gun. Generally speaking, this speed allows people to shoot at each other with airsoft guns safely, under certain conditions. The first condition is eyewear.
Never, ever, shoot at someone who is not wearing proper eye protection. Proper eye protection means eye goggles rated at least ANSI Z87.1 or paintball goggles. Proper eye protection is
not military sun/dust/wind goggles, ski goggles, or shop goggles. Do not risk your own eyes or take on liability for your friend's eyes. Always wear proper eye protection when shooting airsoft guns! Read more about
eye protection.
Also please be aware of the speeds at which all airsoft guns used in an airsoft game are shooting. Typical out-of-the-box airsoft guns shoot at ranges anywhere from 250 feet per second to 350 feet per second. Airsoft guns can be modified to shoot faster. Speeds between 375 feet per second and 400 feet per second are usually the maximum speeds US airsoft teams will allow. Make sure that anyone firing an airsoft gun over 400 feet per second is experienced, can accurately judge distance, and does not engage targets at close range. Never mix real bb guns into an airsoft gun game. If you are unsure of an airsoft gun's firing speed either buy a chronograph to measure the speed or simply do not allow it at a game.
The simplest rule to remember with airsoft guns is to treat them as real guns. An accidental discharge at close range can have any number of damaging results including, but not limited too, broken teeth and damaged eyes.
When transporting your gun to and from a game carry it in a gun case. Not only is a gun case the safest means of transportation it also naturally protects your gun (airsoft guns can be quite fragile) and makes a great place to store airsoft pistols and spare magazines. For many areas a gun case is the only way to legally transport your airsoft gun. Remember, it is very difficult to visibly distinguish an airsoft gun from a real gun.
Many people are concerned about the use of airsoft guns in crimes. A criminal is a criminal and will use whatever means they can to break the law. I would prefer a less dangerous criminal with an airsoft gun to a criminal armed with a real gun and the capability to kill innocent people.
Don't let any of these safety issues scare you away. Airsoft is not a dangerous sport as long as everyone playing understands safety. If you can not follow these rules please try another outdoor sport. When everyone follows the rules airsoft is just as safe as paintball. In 3 years of playing I never saw any serious accident. On a few occasions a BB at close range has drawn blood, but even that is rare. I have played in games with 50+ people without incident.
Last, but not least, before you play an airsoft game make sure that the airsoft teams that you are playing with have strict rules concerning safety and feet per second limits for guns involved. Good Luck!