CFR > Title 30 - Mineral Resources > CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR > SUBCHAPTER O—COAL MINE SAFETY AND HEALTH (parts 70 to 90) > PART 77—MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES > SUBPART O—Personnel Hoisting (§77.1400 to §77.1438) > 77.1434—Retirement criteria.

77.1434—Retirement criteria.

Unless damage or deterioration is removed by cutoff, wire ropes shall be removed from service when any of the following conditions occurs:
(a) The number of broken wires within a rope lay length, excluding filler wires, exceeds either—
(1) Five percent of the total number of wires; or
(2) Fifteen percent of the total number of wires within any strand;
(b) On a regular lay rope, more than one broken wire in the valley between strands in one rope lay length;
(c) A loss of more than one-third of the original diameter of the outer wires;
(d) Rope deterioriation from corrosion;
(e) Distortion of the rope structure;
(f) Heat damage from any source;
(g) Diameter reduction due to wear that exceeds six percent of the baseline diameter measurement; or
(h) Loss of more than ten percent of rope strength as determined by nondestructive testing.