Section R. 408.41217 - Planking and scaffold platforms generallyRule 1217.
(1) If wood planks are used for a work platform, then the planks shall be scaffold-grade lumber that has a minimum of 1,500 pounds per square inch fiber stress value. The planks shall be not less than 2 inches by 10 inches. The platform shall consist of a minimum of 2 planks laid side by side. Each platform on all working levels of scaffolds shall be fully planked or decked between uprights where practicable. Spaces between the platform and the uprights shall not be more than 9 1/2 inches. The maximum permissible spans for 2- by 10-inch or wider planks are as follows: | Material full thickness undressed lumber | Material nominal thickness lumber |
Working load (per square foot) | 25 | 50 | 62 | 75 | 25 | 37 | 50 | 62 |
Permissible span (feet) | 10 | 8 | 7 | 6 | 8 | 7 | 6 | 4 |
(2) Wood scaffold planks, laminated planks, manufactured work platforms, and picks that are found to be defective shall be removed from service and shall not be used.(3) A manufactured pick shall be permanently marked or tagged to indicate the maximum working load and shall not be less than 14 inches wide when used in single width, except that a ladder jack scaffold may be used with a minimum 12-inch manufactured pick.(4) Platform planks shall be laid with their edges together so the platform is tight and does not have spaces through which tools or fragments of materials can fall.(5) Planking shall comply with all of the following provisions: (a) Extend over the end bearer not less than 6 inches, but not more than 12 inches.(b) Be cleated or otherwise fastened to prevent shifting and be uniform in thickness, except where lapped as prescribed in subrule (8) of this rule.(c) Where 16-foot planks are used as prescribed in subrule (7) of this rule, tie downs are not required unless wind uplift may occur.(6) Hook-on-type manufactured work platforms may be used if they are secured to the bearer.(7) Where planks are lapped, each plank shall lap its bearer not less than 6 inches, which will provide a minimum overlap of 12 inches.(8) Where a scaffold turns a corner, the planks shall be laid to prevent tipping. The planks that meet the corner bearer at an angle shall be laid first and shall extend over the diagonally placed bearer far enough to have a good bearing, but not far enough to tip. The planks that run in the different direction shall be laid so as to extend over the rest on the first layer of planks.(9) When moving a platform to the next level, an employee shall leave the old platform undisturbed until the new platform supports have been set in place and are ready to receive the platform planks.(10) A platform shall not deflect more than 1/60 of the span when loaded.(11) A wood platform shall not be covered with opaque finishes, except that platform edges may be covered or marked for identification. A platform may be coated periodically with wood preservatives, fire-retardant finishes, and slip-resistant finishes; however, the coating may not obscure the top or bottom wood surfaces.(12) The front of a platform shall be not more than 14 inches from the face of the work unless a guardrail system is erected along the front edge, or unless a personal fall arrest system is used pursuant to Construction Safety Standard Part 45. "Fall Protection," as referenced in R 408.41201, except that the maximum distance from the face of the work for plastering and lathing operations shall be not more than 18 inches.Mich. Admin. Code R. 408.41217
1981 AACS; 1990 AACS; 1998-2000 AACS; 2013 AACS; 2016 AACS; 2018 MR 23, Eff. 12/19/2018