A. Materials and Design: Piping, valves and fittings for flammable liquids shall be designed for the working pressure and structural stresses to which they may be subjected. They may be of steel or other materials suitable for use with the liquid being handled. Pipe wall thickness determined in accordance with section 3 of the American Standard Code for Pressure Piping (A.S.A. B31.1) shall be deemed to comply with this Section; except that carbon steel pipe shall not be thinner than standard wall thickness listed in the American Standard for wrought-iron and wrought-steel pipe (A.S.A. B36.10). (1968 Code, §21.120)
B. Piping Runs: Piping shall be run as directly as possible and proper allowance made for expansion and contraction. (1968 Code, §21.121)
C. Piping Above Ground:
1. Pipes shall not be surrounded or covered by cinders or other material of corrosive effect, but preferably should be laid in sand, and where carried in conduit, the openings of such conduit must be fully protected to prevent escape or liquid under dangerous conditions.
2. Pipe lines buried on railroad property shall be laid at a depth of not less than three feet (3'); where they pass under tracks, they shall be laid at least four feet (4 ') below the bottom of ties.
3. Piping buried in Village streets or other area where other pipe lines are carried shall be placed in conduit. Joints of conduit shall be sealed to prevent leakage and pitch shall be toward tank yard.
4. Underground piping shall be coated with asphaltum or corrosion resisting material. (1968 Code, §21.122)
D. Joints in Pipes: Joints may be welded or of the ordinary screw type; if the screw type, they shall be made with litharge and blycerine, lamp black or shellac. (1968 Code, §21.123)
E. Tests of Piping: Piping after installation shall be tested at a pressure of fifty percent (50%) in excess of the working pressure and shall be proven tight. Test shall continue thirty (30) minutes. (1968 Code, §21.124)
F. Normal Valve in Pipes: Each pipe attached to a tank shall be provided with a valve at the tank, with no branches or outlets, between the tank and the valve.
In case two (2) or more tanks are cross-connected, there shall be a valve at each tank in each cross-section. Tanks with different classes of liquids shall not be cross-connected. (1968 Code, §21.125)
G. Emergency Internal Check Valves: In addition to any normal valves, there must be an extra valve at each pipe line connection to any tank below normal liquid level (regardless of when installed). Such valve must contain an effective heat actuated device which, in case of fire, will automatically close the valve to prevent the flow of liquid from the tank, even though the pipe lines are broken from the tank. These extra valves are not required in crude oil tanks in oil fields, or tanks at refineries, or on tanks at terminals which are equipped with a swing line or where facilities are provided to transfer the contents of the tank to another tank in case of fire. (1968 Code, §21.126)