Abstract: At approximately 1:10 p.m. on April 18, 1990, Employee #1 and a coworker were dismantling a 72 ft lattice boom from a 35 ton Link-Belt LS98 crawler crane for removal to another site. The crane boom had been lowered to an approximate height of 4 ft. The boom was held aloft by the boom pendants and was not blocked or cribbed or otherwise secured against dropping. The coworker, who was the crane operator, placed a block of wood under the boom bridle, but the bridle was not secured to the boom. Employee #1 was under the boom's tip section at the pin connection lugs. He removed the cotter pins from the boom pins and then pounded out the boom pins. As the last boom pin was removed the boom collapsed down on him. Employee #1 suffered multiple injuries to the head and neck and was pronounced dead at the site. The accident occurred because Employee #1 was allowed to work under the boom and remove the lower boom pins before the boom was blocked or cribbed.