Ohio Revised Code Title I. State Government § 153.10

After the plans, bills of material, specifications of work, estimates of cost in detail and in the aggregate, life-cycle cost analysis, form of bid, bid guaranty, and other data that may be required are approved and filed with the owner as defined in section 153.01 of the Revised Code, no change of plans, details, bills of material, or specifications shall be made or allowed unless the same are approved by the owner as defined in section 153.01 of the Revised Code. When so approved, the plans of the proposed change, with detail to scale and full size, specifications of work, and bills of material shall be filed with the original papers. If such change affects the price, the amount thereof shall likewise receive such approval.