Hatchets are notorious for injuries because of their short handle length. They are like an extension of your hand. Anywhere you hand can go, the sharp edge of a hatchet can go. You can get some really crazy glancing blows that can send your hand towards many different parts of your body like your thigh or foot.
I consider tomahawks to be much safer because of their long handle. Anything with a handle length around 19 inches (like the granfors bruks small forest axe)is very safe provided that you chop while kneeling. It allows a 2 handed group which further limits your swing and the length is sufficient enough that any glances go directly in the ground. 19 inches is probably the safest length for any axe, provided that you always use it kneeling. 10-12 inch hatchets are the most dangerous.
Then there are 26 inch boys axes that are very safe, provided that you always keep the edge of the axe more or less parallel to the ground when bring down crosscuting chops. But really, a 26 inch axe is way overkill for most backpackers outside of winter.
Either way, these tools can be safe to use if you follow certain rules, pay attention at all time, and don't do ridiculously stupid things. 95% of all edged tool injuries are going to be from doing something completely stupid. With safe use you can use these tools for your entire life and a serious injury is unlikely to ever happen. But it still can happen and create extremely bad injuries.



