If you have a load that presents a hazard you are to equip the forklift with a vertical load backrest extension per ITSDF B56.1-2012 para 4.5.2. The design has two parameters:
7.28.1 The load backrest extension, if provided, should have height, width, and size of openings sufficient to minimize the possibility of the load falling toward the mast when the mast is in a position of maximum rearward tilt.
7.28.2 The load backrest extension, if provided, shall be constructed in a manner that does not interfere with good visibility, and size of openings should not exceed 150 mm in one of the two dimensions.
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