All fuel storage tanks or cylinders shall be permanently installed and securely fastened in place and shall not be located: inside or beneath the mobile-home, or less than fifteen (15) feet from the mobile-home exit-entrance. Fuel storage shall be permitted in tanks or containers mounted on an incombustible frame at the rear of the mobilehome. Fuel containers shall not exceed three hundred (300) gallon capacity unless approved by the city council. (Prior code § 23-2-35)