Page 87 - Vessel Sanitation Program 2018 Construction Guidelines
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VSP 2018 Construction Guidelines
Point sample cocks down and identify them with the appropriate tank
number.
22.7.2 Storage Tank Access Hatch
22.7.2.1 Installation
Install an access hatch for entry on the sides of POTABLE WATER
TANKS.
22.7.3 Storage Tank Water Level
22.7.3.1 Automatic
Provide an automatic method for determining the water level of
POTABLE WATER TANKS. Visual sight glasses are acceptable.
22.7.4 Storage Tank Vents
22.7.4.1 Location
Ensure that air-relief vents end at least 1,000 millimeters (40 inches)
above the maximum load level of the vessel.
Make the cross-sectional area of vents equal to or greater than that of
the tank filling line.
Position the end of the vents so openings face down or are otherwise
protected, and install a 16-mesh corrosion-resistant screen.
22.7.4.2 Single Pipe
A single pipe may be used as a combination vent and overflow.
22.7.4.3 Vent Connections
Do not connect the vent of a POTABLE WATER TANK to the vent of
a tank that is not a POTABLE WATER TANK.
22.7.5 Storage Tank Drains
22.7.5.1 Design
Design tanks to drain completely.
22.7.5.2 Drain Opening
Provide a drain opening at least 100 millimeters (4 inches) in diameter
that preferably matches the diameter of the inlet pipe.
22.7.5.3 Suction Pump
If drained by a suction pump, provide a sump and install the pump
suction port in the bottom of the sump.
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