Ratings in this catalogue are applicable only to new products. The safe working load (S.W.L.) or working load limit (W.L.L.) of each Blue Line-block may be affected by wear, misuse, overloading, corrosion, deformation, intentional alteration and other use conditions.   Working loads shown are the maximum load the block is authorized to support under normal environmental conditions, chock loading and abnormal conditions must be taken into account when selecting the blocks. Regular inspection must be conducted to ensure the equipment continues to meet the required standard.   Blue Line blocks generally are intended for tension or pull. Side-loading must be avoided,as it excerts additional force or loading for which the product is not designed to accommodate.   Welding of or to load supporting parts or products can be hazardous. Knowledge of materials, heat-treatment and welding procedures is necessary for proper welding. The Blue Line should be consulted for information.