Nov 25, · Rule of Thumb for Outrigger Support - Crane Tech Nowhere in OSHA does it say that you will be ok if you use the rule of thumb for cribbing, instead in 1926.1402 OSHA states: that cranes must be assembled on ground that is firm, drained and graded sufficiently, in njunction with supporting materials, such as blocit, cribbing, pads, or mats