Level 1 factor | Level 2 factors of AHP structure for tower crane accident cab-tower crane |
Dismantling work (F1) | F11: Poor understanding of risk factors during dismantling process F12: Bad tightening of bolts F13: Low skill level of dismantling workers |
Lifting work (F2) | F21: Poor management of lifting objects and control of surroundings F22: Poor tying of the sling leg F23: Operator’s bad visibility |
Erection work (F3) | F31: Bad bolting brace/mast/telescopic F32: Failure to comply with safety rules and work guidelines for erection work F33: Insufficient skill in worker for erection work |
Prime contractor’s management (F4) | F41: Inappropriate personnel and equipment placement F42: Poor subcontractor technology management by process F45: Insufficient safety management of equipment and personnel |
T/C machine (F5) | F51: Equipment aging F52: Crane operation error or failure F53: Problems of overseas parts procurement |