Vinctor, for any of us who grew up in suburbia, it's not just that we never learned, either through direct teaching or observation, how to lift, but how to use many common farm/homestead tools. I learned a much better way of using a shovel and fork from reading a book. There is a difference between a long handled and a "D" handled shovel, and they come in different shapes and using the right tool for certain jobs can make a huge difference. But when I first started to garden, a shovel was a shovel, (what - you can use a file to sharpen a shovel?)
The worst part was an embarrassing lesson in how to lift heavy objects, by the physical therapist with everyone watching
"1) I endorse the emphasis on safety. It doesn't take long to bleed to unconsciousness. Get used to the idea that its better to send a false alarm then for someone to find you dead from a missing toe. If its deeper than an inch, or the puddle is bigger than a pancake or it burbles up like a clogged water-fountain, take a ride in an ambulance, let them decide how bad it is. "
If you are going to work with lines under tension remember (chains, ropes, straps, cables), if they are under-tension they can be storing a tremendous amount of force, which can, if they snap, accelerate the now-free ends faster than anyone can react. You won't know its happened until its over. I've seen a 5" diameter tree CUT IN HALF by a snapped chain from a tractor pulling a second tractor out of mud. Sounded like an explosion. I have heard about people getting cut in half by snapped cables.
1) know the rated capacities of every part that is under tension, from pulleys, to shackles to nuts and bolts.
2) put a shear-bolt, or put the weakest link in your system where you want it to fail, so that if something goes wrong, the failure point is known and the failure doesn't put you in danger. I put my shear bolt right at the stationary end of the come-along, and that is right next to the tree I'm felling. If it snaps, the come-along is pulled away from me toward one anchor tree, and the other end is pulled away from me, around the target tree and toward the other anchor tree.
3) Use a tension guage so you can stay well bellow the rated tension. in a system where 1.5 tons in the lowest rated part, I use about 500lbs of tension. that is plenty on a small tree. This does not replace properly planning your hinge-cut, and it is not a good way to cope with a large tree that is leaning. this is for a tree where there isn't enough diameter to get a wedge in.
I'll second that verify - my spouse nearly electrocuted himself discovering that the idiot who wired the house we bought had mixed up the wires so that the baseboard heaters which require 220 Volts were hooked up to 2 different sets of paired breakers instead of on a single set of paired breakers. He turned off one paired breaker, the heater appeared to be off, so he carried on. We had the heaters off for painting. He covered the wire ends and put a plate over the box and we rely on the wood stove for heat - and he bought brushes so he'd clean the chimney regularly!! The moral here is that you can't even trust that a house that "passed an electrical inspection" is actually safe.
VERIFY with meters & such that it is truly de-energized before proceeding.