Section R. 408.41127 - Single and double-cleat ladders generallyRule 1127.
(1) A job-built ladder shall not be more than 24 feet in length. If the length of a required job-built ladder would be more than the maximum length, 2 or more separate ladders shall be used and shall be offset with a platform between each ladder that is not supported by the ladders. Ladders used with a platform shall be secured at the top and bottom.(2) The platform shall be designed to support 4 times the intended load. Guardrails and toeboards, as prescribed in Construction Safety Standard Part 45 "Fall Protection," as referenced in R 408.41102a, shall be erected on the exposed sides of the platform. Rails shall extend above the top landing at least 36 inches but not more than 42 inches to provide a handhold for mounting and dismounting, and cleats shall be eliminated above the landing level. When 2 or more separate job-built ladders are used with a platform, the ladders shall be completely offset from each other and the minimum horizontal distance between adjacent side rails shall be 6 inches.(3) Side rails of a job-built ladder shall be continuous.(4) Each cleat of a job-built ladder shall be a continuous member.(5) A wood cleat shall be not less than nominal 1-inch by 4-inch construction grade lumber for a cleat less than 20 inches in length and not less than nominal 2-inch by 4-inch construction grade lumber for a cleat from 20 inches to 50 inches in length. Knot-free lumber shall be used for cleats.(6) The cleats shall be uniformly spaced 12 inches top to top. A cleat shall be attached to the narrow face of each side rail using 2 10-d nails for nominal 1-inch by 4-inch cleats or 2 16-d nails for 2-inch by 4-inch cleats .(7) Filler blocks shall be used on the rails between cleats. Filler blocks of the same thickness as the cleats shall be inserted between cleats and butted tightly against the underside of each cleat.(8) Side rails shall not be cut into house cleats.Mich. Admin. Code R. 408.41127
1979 AC; 1990 AACS; 1996 AACS; 2015 MR 23, Eff. Dec. 9, 2014