(a) The provisions of this section shall not apply to buildings each occupied by one (1) tenant and used for the processing or manufacturing of flammable liquid, provided such buildings are adequately isolated from other premises and do not present a conflagration hazard to the community.
(b) Except as provided in subsection (a) hereof, tanks for Class III liquid larger than sixty (60) gallon capacity shall not be located above the lowest story of any building. No inside storage tank for Class III liquid shall be located within seven (7) feet horizontally of any open flame.
(c) In buildings of Class III, exterior protected construction, or Class IV, wood construction, the nominal aggregate capacity of such tanks for Class III liquid shall not exceed five thousand (5,000) gallons unless installed as provided in subsection (e) hereof.
(d) In buildings of Class I, fireproof, or Class II, incombustible construction, the nominal aggregate capacity of such tanks for Class III liquid shall not exceed fifteen thousand (15,000) gallons unless installed as provided in subsection (e) hereof.
(e) In any building, if within or buried below a fire-resistive detached room cut off vertically and horizontally in an approved manner by means of an incombustible separation having a fire resistance rating of not less than four (4) hours, the nominal aggregate capacity of such tanks for Class III liquid shall not exceed fifty thousand (50,000) gallons, with no individual tank capacity extending twenty-five thousand (25,000) gallon capacity. Such room shall be so constructed and openings to such room shall be so located that the room will serve as a dike to retain any leakage or seepage.
(f) Except as provided in subsection (a) hereof, tanks for Class III liquid located inside buildings shall not exceed two hundred seventy-five (275) gallons individual capacity or five hundred fifty (550) gallons aggregate capacity in one (1) building or fire area unless installed at least three (3) feet below a concrete floor of the lowest floor level, or installed in the lowest story within or below a fire-resistive detached room as provided in subsection (a) hereof, or in an enclosure or casing constructed as follows:
(1) The walls of the enclosure shall be constructed of reinforced concrete at least six (6) inches thick or of brickwork at least eight (8) inches thick, and shall be bonded to the floor. The space between the tank and the enclosure shall be completely filled with sand or well tamped earth. When the floor or other construction immediately above the tank is of fire-resistive construction capable of safely sustaining a load of one hundred fifty (150) pounds per square foot, the walls of the enclosure shall be carried to a height not less than one (1) foot above the tank and the space above the tank filled with sand or well tamped earth to the top of the wall; otherwise the enclosure shall have a top of reinforced concrete at least five (5) inches thick, or a top of equivalent construction.
(2) Instead of the enclosure described in subsection (f)(1) hereof, the tank may be encased in reinforced concrete not less than six (6) inches in thickness, applied directly to the tank so as to completely eliminate any air space.
(Ord. No. 991-49. Passed 6-27-49, eff. 6-27-49)