New Rope Tensile Strengths: New rope tensile strengths are based on tests in accordance with ASTM Test Method D-4268 on new and unused rope in laboratory condition.
Working Loads: Working loads are for rope in good condition with approximate splices, in non-critical applications, under normal service conditions. Working loads should be exceeded only with expert knowledge of conditions and professional estimates of risk. Working loads should be reduced where life, limb, or valuable property is involved, or for exceptional service conditions such as shock loads, sustained loads, etc.
48 North Marine typically uses 10% - 12% for WLL for rope and 20% for hardware where break/tensile strength is provided by the manufacturer.