Tanks other than the fuel tanks of tank trucks shall comply with the following provisions:
(a) Material, Capacity and Gauge. Except as hereinafter provided, tanks shall be constructed throughout of open hearth or blue annealed steel, of a thickness and gauge in accordance with the provisions of the following table:
Aggregate Capacity (Gallons) |
Shell U.S. Standard Gauge | Head U.S. Standard Gauge |
Up to 600 | 14 | 14 if bilged or corrugated, otherwise 12 |
601 to 1,200 | 12 | 12 if bilged or corrugated, otherwise 10 |
Over 1,200 | 10 | 8 |
Tanks exceeding 1,200 gallons in capacity may be constructed with 12-gauge shells and 10-gauge heads; provided, however, that they are subdivided into compartments of 600 gallons or less capacity, and are mounted on chassis equipped with low-pressure balloon pneumatic tires. Other metals of equivalent strength to the gauge of open hearth or blue annealed steel required by the above table may be used in lieu of open hearth or blue annealed steel.
(b) Joints. Shell and head joints shall be welded, riveted and welded, brazed or riveted and brazed, riveted and caulked or made tight by some equally effective process.
(c) Test. Each tank or compartment shall be tested and proven tight at a pressure of five pounds or more to the square inch.
(d) Tank Outlets. Outlets shall be substantially made and attached so as to prevent breakage at the outlets and shall be attached so as to permit complete drainage.
(e) Bulkheads. Tanks with compartments carrying liquids of different classes shall be provided with an air space between compartments. Such air space shall be maintained with drainage facilities.
(f) Compartments Required. Tanks for flammable liquids of Class I as specified in Section 15-24-020 in excess of 2,500 gallons each. This requirement shall not apply to tanks for transportation in bulk between cities; provided, however, that such tanks shall not be used for distribution within the city limits.
(g) Attachment of Tanks. Tanks shall be adequately supported and shall be securely bolted or clamped to the frame of the vehicle.
(h) Vents. Each compartment shall be equipped with a vacuum and pressure operating vent with a minimum effective opening of forty-four hundredths square inches. Each compartment carrying Class I flammable liquids, as specified in Section 15-24-020, shall be provided with a vent equivalent in free opening to that provided by a circular hole one and twenty-nine thirty-seconds inches in diameter. If such vent incorporates a fusible element, the fusing temperature of such element shall not exceed 200 degrees Fahrenheit.
(i) Draw-off Valves. All draw-off valves or faucets shall have threaded or equally effective connection for fill pipe hose. Such valves or faucets shall be adequately guarded against damage by collision.
(j) Emergency Discharge Control. Each compartment of a gravity discharge tank used for the transportation of Class I flammable liquids shall be equipped with a reliable shutoff valve located inside the shell of the tank in the compartment outlet; and, except during delivery operations, such valves shall be kept closed. The operating mechanism for such valves shall be provided with a secondary control, remote from the tank-filling parts and discharge faucets, for use in event of accidents or fire during delivery operations and such control mechanism shall be provided with a fusible section which will cause the valves to close automatically in case of fire. In every case there shall be provided, between the shutoff valve seat and discharge faucet, a shear section which will break under strain, unless the discharge piping is so arranged as to afford the same protection and leave the shutoff valve seat intact.
(Prior code § 129.1-99)