Abstract: At approximately 8:00 a.m. on May 8, 1991, Employee #1 was helping bend and install conduit. The conduit was being bent on the third floor, in back of the metal stairs leading up to the second level of the third floor. At the left side of the stairs and 16 in. from the edge of the stairs was the 8 ft. 7 in. by 12 ft 3 in. third floor hoistway opening. A piece of metal channel had been tack welded to the base of the stairs and to the metal at the edge of the hoistway opening. The hoistway opening guardrails consisted of a 3/8 in. wire rope top rail and intermediate rail. The top rail was slack. At the right hand side of the stairs slag was falling from welding and cutting above. Employee #1, who was on his way to the second level of the third floor, tripped on the piece of metal channel. Consequently, he fell over the slack top rail, then fell 14 ft to the metal cover over the second floor hoistway opening. Employee #1 was hospitalized.