Logging and commercial fishing are usually tied for the most dangerous jobs in America, at about 150 deaths per 100,000. People get hurt, and sometimes killed, by chain saws, but most deaths are the result of falling objects. Gear is available to make the logger's job a little safer. The pants shown here have pockets in the front of the legs to hold Kevlar pads like the one on the left, designed to jam a chain saw and keep cuts from being so severe. Hard hats are available with face screens to give some protection from flying chips, and ear muffs to save the logger's hearing. The hat on the right was being worn by a logger when a branch fell down and broke over his head. The man was driven down to his knees and the hat split across the crown. The hat had to be discarded -- the man lived.
Wedges are used to force a tree to fall where the logger wants. Originally they were made of wood or steel, and often were squeezed back out of a cut in frozen wood, even when "ragged" (roughened with a cold chisel). Plastic wedges won't hurt the cutting chain and have ridges molded in to make them less likely to jump out of a cut.
Before the advent of plastic, loggers had 'tin hats' which were actually pressed out of aluminum. Although long banned in the industrial setting because of electrical concerns, they are still used in the woods today. There was also a generation of soft aluminum alloy wedges that preceded the plastic ones. They were hard enough to drive, but soft enough that they didn't ruin a saw chain if you backed the saw into it..