LOOKING FOR AN AIR LEAK BY THE AIR DRYER ON A LOADER. HAD ANOTHER MAN START THE LOADER TO BUILD UP AIR PRESSURE TO SEE WHAT HAD TO BE RE- PAIRED. THE TOP OF THE AIR DRYER BLEW OFF, CAUSING INJURY TO THE HEAD. HARDHAT WAS BEING WORN AT THE TIME OF INJURY. 6 STITCHES TO THE FOREHEAD CAUSED FROM THE HARDHAT.