Most of my life since I entered the boy scouts as a kid I have carried a pocket knife of some sort, but when I started a business that required me to get (cell) tower climbing and rescue climbing certified (and insured), and then climb those towers from time to time, I started carrying a little larger knife that was not floating around with my keys or pocket change, but instead either clipped to my pocket when on the ground, or if I was in a climbing harness, clipped inside the chest strap so it couldn't get snagged. It was also always accessable, and openable with a single hand.
Since I haven't been up on a cell tower in roughly 4 years (sold the business), I don't carry as large of a knife anymore (my current knife blade is the width of my hand), but I still carry a folding knife clipped to my pocket 90% of the time, and often also a rigging knife in a cargo pocket of my shorts when on someone else's boat. If I am tethered to something, it's a safe bet I have a knife somewhere on my person that can cut that tether in an emergency.
Since I haven't been up on a cell tower in roughly 4 years (sold the business), I don't carry as large of a knife anymore (my current knife blade is the width of my hand), but I still carry a folding knife clipped to my pocket 90% of the time, and often also a rigging knife in a cargo pocket of my shorts when on someone else's boat. If I am tethered to something, it's a safe bet I have a knife somewhere on my person that can cut that tether in an emergency.