Compressed air weapons are firearms in which air is compressed and stored in a pressure vessel. The stored compressed air is released via a valve when a shot is to be fired, thus propelling the projectile. In spring-loaded guns, on the other hand, a spring-loaded piston creates a cushion of air that propels the bullet. The third system is compressed gas guns, which use a cold propellant gas such as carbon dioxide to propel the bullet - no cocking or compressing action is required by the shooter.
These systems are colloquially referred to as air rifles or air pistols.
Compressed air weapons, which do not have more than 7.5 joules of muzzle energy, are marked in Germany with the symbol "F in a pentagon" and are freely available for sale from the age of 18. Also not subject to purchase are compressed air weapons that were manufactured and put on the market before 01.01.1970 and those that were manufactured and put on the market before 02.04.1991 in the territory of the GDR. In the case of the last two mentioned, the weapons may also have a muzzle energy exceeding 7.5 joules.
Compressed air weapons that do not fall into any of these categories are subject to licensing and must be registered on a weapons ownership card.