standard ladder rung
The minimum clear length of rungs or cleats shall be 16 inches. 1910.27(b)(1)(iv) Rungs, cleats, and steps shall be free of splinters, sharp edges, burrs, or projections which may be a hazard. 1910.27(b)(1)(v) The rungs of an individual-rung ladder shall be so designed that the foot cannot slide off the end.