First,
firearms are incapable of doing anything unless influenced by an outside source. A firearm in and of itself is simply a mechanical instrument that is an inanimate object. The first and primary thought to consider is if you are not completely confident and/or comfortable or in the right frame of mind with handling a firearm then, the safest thing to do is leave it alone entirely. Regardless of age, this applies to everyone, but specifically to children.
Second,
the assumption that a firearm is unloaded is the most common and costly mistake individuals tend to make when handling a firearm. You always treat all firearms as if they are loaded. If you're planning to handle and/or operate a firearm in anyway then, adopt the philosophy and mindset that all firearms are loaded (also referred to as "live") and ready to fire. If you treat each firearm with the proper amount of respect, you will decrease or even deter the likelihood that a negligent discharge might occur.
Third,
a bullet (discharged cartridge) can only exit from one point on a firearm, the muzzle. Once the bullet exits the barrel through the muzzle, the bullet's trajectory will then travel in a straight line until it impacts 'something' in its line of path or runs out of inertia. The muzzle is considered the most dangerous point of any firearm and you should always ensure that you have absolute control over where it is being pointed. This is a very simple concept, if the muzzle is pointed at the ground or in a safe direction, then a discharge can't impact, harm, or destroy 'anything'. Always ensure the muzzle is being pointed in the safest possible direction or, the very least, in the direction of something that you have no doubt what-so-ever that you are willing to destroy.
Fourth,
firearms are mechanical instruments designed to shoot when the trigger is pulled, pressed, or engaged. Because of this one fact, you need to adopt the mindset that the best practice to prevent a firearm from having a negligent discharge is to ensure you are keeping anything and everything away from the trigger itself. Therefore, when handling a firearm, never place your finger (in most cases the index finger) on the actual trigger until the firearm is drawn, set, pointed in an absolutely safe direction and you as the shooter are completely ready to fire, period.
Fifth,
firearms are precision instruments engineered meticulously with many mechanical moving parts to endure harsh environments and weather, or other conditions while ensuring durability, precision and accuracy. The sequence of fire generates a considerable amount of pressure on a firearms internal mechanical parts, particularly the tension on springs which were designed with extreme-tensile strength. If any object, piece of clothing, or part of your body gets in the path of these mechanical moving parts during the sequence of fire, you're risking the potential of severe injury. As all other tools, firearms were engineered & designed with specific points to grab, grip, and hold the mechanical instrument in order to operate safely and efficiently. If you are not entirely sure or confident where those positions are then, simply refer-back to the first point of this lesson and leave it alone entirely.
A quick recap! Firearms don't do anything by themselves, the only assumption you should ever make about a firearm is that it is loaded and ready to fire. Bullets can only exit from the muzzle and travel in straight lines making the muzzle the most dangerous part of a firearm. The best way to prevent a gun from firing is to ensure nothing ever comes close to the trigger, and firearms that have moving parts are going to move the way they're designed whether something is in the way or not.
These five principles are at the very essence of what the key fundamentals are in regards to firearm safety rules. Before we explore these rules in further depth and elaborate the best practice methods of applying them, we must first begin with your mental approach, your mindset, your actual frame of mind as well as the required clarity necessary that ties into firearms safety.
Whenever handling a firearm, you must remember to be in an elevated state-of-awareness and always be respectful and aware of the harm a firearm can do. While being mindful, attentive to your surroundings and aware of all the details, you're much more likely to recognize something alarming, unsafe or even dangerous. With the proper mindset, you'll be more likely to avoid the most common influences that lead to firearm related accidents and deaths.