Footings, splices, uprights, track timbers, ledges, sills, laps, bracing, flooring and all other wood components of rides, devices and structures shall be inspected for deterioration, breaks, or fractures. Emphasis shall be given to insuring tight nails, bolts, lag bolts and other fasteners. A minimum of eighteen (18) inches of soil, with respect to grade, may be removed around piling or wood members embedded in dirt for support to check deterioration. When wood piling requires replacement, ground level concrete piers shall be used. Wood members found to be defective shall be replaced with material of equal strength and capacity.
Okla. Admin. Code § 380:55-13-8