Treat every gun as though it can fire at any time. The “safety” on any gun is a mechanical device which, like any such device, can become inoperable at the worst possible time. Besides, by mistake, the safety may be “off” when you think it is “on.” The safety serves as a supplement to proper gun handling but cannot possibly serve as a substitute for common sense. You should never handle a gun carelessly and assume that the gun won’t fire just because the “safety is on.”
Never touch the trigger on a firearm until you actually intend to shoot. Keep your fingers away from the trigger while loading or unloading. Never pull the trigger on any firearm with the safety on the “safe” position or anywhere in between “safe” and “fire.” It is possible that the gun can fire at any time, or even later when you release the safety, without your ever touching the trigger again.
Never place the safety in between positions, since half-safe is unsafe. Keep the safety “on” until you are absolutely ready to fire.
Regardless of the position of the safety, any blow or jar strong enough to actuate the firing mechanism of a gun can cause it to fire. This can happen even if the trigger is not touched, such as when a gun is dropped. Never rest a loaded gun against any object because there is always the possibility that it will be jarred or slide from its position and fall with sufficient force to discharge.
The only time you can be absolutely certain that a gun cannot fire is when the action is open and it is completely empty. Again, never rely on your gun’s safety. You and the safe gun handling procedures you have learned are your gun’s primary safeties.