WAC 296-78-71003. Floor and wall openings

(1) All floor and wall openings, either temporary or permanent, must be protected in accordance with chapter 296-880 WAC. (2) The area under floor openings must, where practical, be fenced off. When this is not practical, the areas must be plainly marked with yellow lines and telltails must be installed to hang within five and one-half feet of the ground or floor level. (3) Where floor openings are used to drop materials from one level to another, audible warning systems must be installed and used to indicate to employees on the lower level that material is to be dropped.