Concrete slabs less than three and one-half (3 ½ ) inches thick may be considered to have an allowable load bearing capacity of three-hundred-fifty (350) pounds per column. The enforcement agency may accept a loading not to exceed five-hundred (500) pounds per column, provided the slab is not less than three and one-half (3 ½ ) inches thick and in good condition. The weight of individual poured concrete footings shall be one and one-half (1 ½ ) times the calculated uplift force. The weight of concrete shall be assumed to be not more than one hundred forty-five (145) pounds-per-cubic-foot.