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Recommended Practices for the Testing and Verification of Spill, Overfill, Leak Detection and Secondary Containment Equipment at UST Facilities <br />7. Using the automatic shutoff device manufac- <br />turer's suggested procedure, examine the drop <br />tube and shutoff valve to determine if product <br />flow will be completely shut off at 95 percent of <br />tank capacity. Make any adjustments necessary <br />to ensure that flow will be completely shut off <br />when the tank is no more than 95 percent full. <br />�. After inspection of the automatic shutoff device, <br />reinstall the drop tube. <br />FIGURE 7-1. Check the drop tube and flapper for dam- <br />age. Make sure that the flapper moves freely and will <br />move into the product flow path. <br />7.1.7 Pass/Fall Criteria. If the automatic shut- <br />off device functions as designed and complete <br />shutoff of product flow is able to occur when the <br />tank is no more than 95 percent full, the automatic <br />shutoff device passes the inspection. <br />If the automatic shutoff device does not function <br />as designed or complete shutoff of product flow <br />is unable to occur until the tank is more than 95 <br />percent full, the automatic shutoff device fails the <br />inspection. <br />7.2 Gall Float Valves. The committee recommends <br />that ball floats be removed from USTs as ove�ll preven- <br />tion devices and another method of overfill prevention be <br />installed. <br />7.2.1 General. Ball float valves are designed <br />to restrict product flow when product in the tank <br />reaches a certain level by restricting vapor flow <br />from the tank ullage. When vapor flow is restricted, <br />pressure builds in the tank ullage, slowing the flow <br />of product into the tank. <br />To operate properly, the ball float valve must be <br />properly installed, positioned at the correct height <br />inside the tank and compatible with UST configu- <br />ration. <br />7.2.2 Purpose. The purpose of this inspection is <br />to verify that the ball float valve is installed prop- <br />erly, operates as designed, and is set to restrict flow <br />when the tank is no more than 90 percent full. <br />FIGURE 7-2. Ball float assembly showing the ball in the <br />open position. The ball will float and cover the vapor <br />path if the product rises above the level of the cage. <br />7.2.3 Inspection Equipment. Test equipment <br />shall include: <br />® equipment to remove the vent restriction device; <br />® tape measure. <br />7.2.4 Description of Inspection. The ball float <br />valve assembly is removed from the tank, inspect- <br />ed for proper operation and measured to ensure that <br />the ball float assembly is the proper dimension to <br />restrict flow into the tank when it is no more than <br />90 percent full. <br />7.2.5 Preparation. Refer to the manufacturer's <br />tank chart for the capacity in gallons, the diameter <br />and the volume of product with respect to product <br />level. <br />E <br />E <br />3 <br />