Abstract: EMPLOYEE #1 WAS DEMOLISHING A SUBGRADE BOILER ROOM USING A "HEADACHE" BALL. ADJACENT TO THE BOILER ROOM VAULT, ON A SEPARATE FOUNDATION, WAS A 30 FOOT TALL AUDITORIUM COMPLETED IN 1986. VIBRATIONS FROM THE DEMOLITION WORK ON THE VAULT FLOOR SLAB, 20 FEET BELOW GROUND, WERE TRANSMITTED TO THE AUDITORIUM, CAUSING THE DECAYED A-FRAME ROOF TO COLLAPSE AND FALL. THE FORCE CREATED BY THE FALLING ROOF PUSHED THE UPPER 15 FEET OF THE SOUTH WALL ONTO THE CRANE, LOCATED 18 FEET FROM THE AUDITORIUM. THE FALLING BRICK STRUCTURE LANDED ON THE CRANE CAB, PINNING EMPLOYEE #1 BETWEEN THE SEAT AND THE CAB WALL. HE WAS TREATED AT THE SCENE AND TRANSPORTED TO JOHNS HOPKINS HOSPITAL, WHERE HE DIED 75 MINUTES LATER.