unintentional roof fall occurred 4300' from 001 mmu 190'long x 20'wide x 10'high (Breakered off) found on exam bolted with 6'tension & 8' point anchor, fell from #1 right to #5 entry, 2' rider at 4' & 12' rider at 10', 90' inby #1648 spad 1st right 2nd S.W. mains