R 408.41542 Wire rope.

Rule 1542. (1) Wire rope used for material hoists, personnel hoists, and elevators shall be removed from service when any of the following conditions exists: (a) In hoisting ropes and running ropes, 6 randomly distributed broken wires in 1 rope lay or 3 broken wires in 1 strand in 1 rope lay. (b) Abrasion, scrubbing, flattening, peening, kinking, crushing, bird caging, or any other damage resulting in distortion of the rope structure and causing loss of more than 1/3 of the original diameter of the outside wires. (c) Evidence of any heat damage from any cause, including damage resulting from a torch or any damage caused by contact with electrical wires. (d) Reduction from nominal diameter of more than 3/64 inch for diameters up to and including 3/4 inch; 1/16 inch for diameters 7/8 to 1-1/8 inches; and 3/32 inch for diameters 1-1/4 to 1- 1/2 inches. (e) In standing ropes, more than 2 broken wires in 1 lay in sections beyond end connections or more than 1 broken wire at an end connection. (2) Hoisting ropes shall be installed in accordance with the wire rope manufacturers' recommendations. (3) A wire rope shall be in compliance with all of the following requirements: (a) The minimum number of hoisting ropes used shall be 3 for traction hoists and 2 for drum- type hoists. (b) The minimum diameter of hoisting and counterweight wire ropes shall be 1/2-inch. (c) Not less than 2 ropes shall be used for the counterweights on the rack and pinion. (d) Safety factors shall be as in Table C “Minimum Factors of Safety for Suspension Wire Ropes”. (e) The following formula shall be used to calculate the allowable gross load: L = SN F L = Allowable gross load S = Manufacturer’s rated breaking strength N = Number of parts of rope F = Safety factor TABLE C MINIMUM FACTORS OF SAFETY FOR SUSPENSION WIRE ROPES Rope speed in feet per minute Minimum Factor of safety 50 7.60 75 7.75 100 7.95 125 8.10 150 8.25 175 8.40 200 8.60 225 8.75 250 8.90 300 9.20 350 9.50 400 9.75 450 10.00 500 10.25 550 10.45 600 10.70