Type C investigation report of crane two-blocking event at 241-SY-101 double-shell waste tank.

摘要

This report summarizes the results of a joint Westinghouse Hanford Company (WHC) and Kaiser Engineers Hanford (KEH) investigation into the June 22, 1993 crane event in SY tank farm. The direct cause of the two-block event was operator error; the operator's concentration was distracted from the area of primary responsibility, which was crane operation. Poor work planning and equipment design were contributing factors in the event. Lack of an adequate supply of rope to use as a tag line added increased complexity to the task. This complexity, in the absence of operator aids or designed interlocks to prevent two-blocking the crane, contributed to the event. The timeliness of event reporting issue appears to center on the completeness of event reporting to the line organization responsible for the facility. The causes of this were inadequate training of the designated person-in-charge (PIC) and no formal requirement for external contractors to notify the facility owner of the event.