Okla. Stat. tit. 61, § 11

A. Unless otherwise provided for by law, all plans and specifications for the erection of public buildings by this state, or any agency or political subdivision thereof, or for any building erected through the use of public funds shall provide facilities for people with disabilities. Such facilities shall conform with the codes and standards adopted by the State Fire Marshal and amended by the Office's promulgated rules. Elevators shall be constructed and installed in said public buildings to the extent deemed feasible and financially reasonable by the contracting authority of the state or such political subdivision. Said codes and standards shall be on file in the Office of Management and Enterprise Services. B. Any building or facility which would have been subject to the provisions of this section but for the fact that it was constructed prior to May 24, 1973, shall be subject to the requirements of this section if additions are made to such building or facility in any twelve-month period which increase the total floor area of such building or facility by twenty-five percent (25%) or more or if alterations or structural repairs are made to such building or facility in any twelve-month period which affect twenty- five percent (25%) or more of the total floor area of such building or facility.