2.20.4 Minimum Number and Diameter of Suspension Means
Where a car counterweight is used, the number of counterweight ropes used shall be not less than two.
The term "diameter," where used in reference to ropes, shall refer to the nominal diameter as given by the rope manufacturer.
The minimum diameter of hoisting and counterweight ropes shall be 4.0 mm (0.156 in.). Outer wires of steel wire ropes shall be not less than 0.21 mm (0.008 in.) in diameter.