PDFWAC 296-880-40075
Crawling board and chicken ladder requirements.
Crawling boards, chicken ladders, and their use must conform with the following provisions: Crawling boards and chicken ladders are not fall protection systems.
(1) Crawling boards must be not less than ten inches wide and one inch thick, having cleats one by one and one-half inches:
(a) The cleats must be equal in length to the width of the board and spaced at equal intervals not to exceed twenty-four inches.
(b) Nails must be driven through and clinched on the underside.
(c) The crawling board must extend from the ridge pole to the eaves when used in connection with roof construction, repair, or maintenance.
(2) Crawling boards must be secured to the roof using ridge hooks or other equivalent means.