• Weight of the load to be lifted. The weight of routine loads of pipes, timber, steel, etc. can often be established from the manufacturer, or supplier, from delivery tickets or by calculation. Where weights of loads cannot be determined, e.g. pile extraction, they must be estimated by a person of experience in such matters,
• The load dimension. The size and shape of the load must be considered together with any lifting point which may be available. An assessment of the center of gravity must also be made to ensure the crane hook is placed above that point,
• The positioning of the load. Many loads may have to be placed at an angle or have one face resting directly on a surface which would prohibit removal of the slings if the more traditional “wrap around” method of slinging was used,
• Headroom. If lifts are to take place in area of restricted headroom, then spreader beams may be more appropriate than other types of slinging methods