820 Cranes and Derricks Safety I

The A/D Director

The A/D director must understand the applicable Assembly and Disassembly procedures. The A/D director must take the following precautions to protect against potential hazards associated with the operation, including:

• Site and ground conditions must be able to support the equipment during Assembly and Disassembly.
• Blocking material must be the correct size, amount, and condition. The blocking must be stacked so as to sustain the loads and maintain stability.
• When used to support lattice booms or components, blocking must be placed appropriately to protect the structural integrity of the equipment, and prevent dangerous movement and collapse.
• When using an assist crane, the loads that will be imposed on the assist crane at each phase of Assembly and Disassembly must be verified as being within its rated capacity.
• The point(s) of attachment of rigging to a boom (or boom sections, jib, or jib sections) must be suitable for preventing structural damage and facilitating safe handling of these components.
• The center of gravity of the load must be identified if necessary for the method used for maintaining stability. Where there is insufficient information to accurately identify the center of gravity, measures designed to prevent unintended dangerous movement, resulting from an inaccurate identification of the center of gravity, must be used.
• The boom sections, boom suspension systems (such as gantry A-frames and jib struts), and components must be rigged or supported to maintain stability upon the removal of the pins.
• Suspension ropes and pendants must not be allowed to catch on the boom or jib connection pins or cotter pins (including keepers and locking pins).
• Steps must be taken to prevent unintended movement from counterweights that are inadequately supported or are being hoisted.
• Each time reliance is to be placed on the boom hoist brake to prevent boom movement during Assembly and Disassembly, the brake must be tested prior to such reliance to determine if it is sufficient to prevent boom movement. If it is not sufficient, a boom hoist pawl, other locking device/back-up braking device, or another method of preventing dangerous movement of the boom (such as blocking or using an assist crane) from a boom hoist brake failure must be used.
• Backward stability must be assured before swinging the upperworks, travel, and when attaching or removing equipment components.
• The effect of wind speed and weather on the equipment must be taken into account.

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