IA (Instrument Air) Flashcards
The reactor is at 100% power. All instrument air compressors are running. IA header pressure is 88 psig and gradually decreasing. Which one of the following states when the reactor should be tripped and the Emergency Operation procedures implemented according to 40AO-9ZZ06,”LOSS OF INSTRUMENT AIR”?
A. If instrument air pressure can not be maintained above 73.5 psig.
B. If the CRS determines that a trip is needed due to reduced instrument air pressure.
C. If instrument air pressure can not be maintained above 85 psig with the Nitrogen Backup Valve open.
D. If instrument air pressure decreases to 65 psig and the Front Standard Turbine Trip Air Relay Dump Valve actuates its low pressure switches.
Answer: B
Given the following conditions: A Loss of Instrument Air has occurred. Nitrogen is supplying the Instrument Air Header. In order to reduce the possibility of Nitrogen buildup in the Auxiliary Building, which of the following actions are taken?
A. Isolate Instrument Air to the Auxiliary Building.
B. Start a Fuel Building Essential Exhaust Fan taking a suction on the Auxiliary Building.
C. Open all Auxiliary and Fuel Building Rollup Doors.
D. Start a Fuel Building Essential Exhaust Fan taking suction on the Fuel Building.
Answer: B
A Loss of Instrument Air has occurred. Nitrogen is supplying the Instrument Air Header. Why are the operators directed to start a Fuel Building Essential AFU and align it to the Auxiliary Building?
A. To ensure that at least one AFU has been aligned before there is not sufficient air (nitrogen) pressure to reposition the required valves.
B. Performing this action will eliminate the requirement of monitoring the lower levels of the Auxiliary Building for nitrogen.
C. The Fuel Building Essential AFU suction valve may freeze up when you attempt to reposition it with nitrogen instead of air, rendering it inoperable.
D. This action will assist in reducing the nitrogen buildup in the lower levels of the Auxiliary Building.
Answer: D
Following a complete Loss of All Instrument Air ( No Nitrogen backup ), which one of the following conditions describes the final status of a Main Steam Isolation Valve with NO operator action?
A. Fails AS-IS, and can only be slow closed.
B. Fails fully OPEN.
C. Fails fully CLOSED.
D. Fails AS-IS, but can be fast closed.
Answer: D
At less than 80 psig instrument air header pressure, the Heater Drain Pump discharge valves will:
A. Fail closed
B. Fail as-is
C. Fail open
D. Remain unaffected, since they are on nitrogen backup
Answer: A
The plant is at 100% power. A gradual loss of instrument air occurs. As instrument air pressure decreases, which of the following events occur first?
A. Feedwater economizer reg valves fail in current position.
B. Main feedwater pump speed decreases.
C. Heater drain tank pump discharge valve fails open.
D. Condensate pump miniflow valves fail open.
Answer: D
A gradual loss of Instrument Air is occurring. The area operator reports a large differential pressure across the in service Instrument Air Dryer. Which one of the following actions should be taken to assist in correcting this problem?
A. Vent the Air Dryers
B. Bypass Air Dryers
C. Shutdown Air Dryers
D. Shift Air Dryers
Answer: D
Instrument air header pressure is 65 psig. The reactor has been manually tripped from 100% power due to plant instability. Based on these conditions, what means of ADV operations are available?
A. only at the remote shutdown panel.
B. normal for one closure only.
C. only local operation in the MSSS.
D. normal operation for > 8 hours.
Answer: D
Reactor power is 100%. All instrument air compressors are running fully loaded. “INST AIR HDR PRESS LO” alarm (7B01B). “INST AIR SYS TRBL” alarm (7B01A). “INST AIR N2 BACKUP VLV OPEN” alarm (7B02B). Which one of the following procedures would appropriately address this situation?
A. Degraded Electrical, 40AO-9ZZ12
B. Loss of Instrument Air, 40AO-9ZZ06
C. Loss of Condenser Vacuum, 40AO-9ZZ07
D. Loss of HVAC, 40AO-9ZZ20
Answer: B
Instrument Air isolation valve IAA-UV-2 has inadvertently closed and will not reopen. N2 backup is available for containment, but not hooked up. Which one of the following describes the expected response of the Reactor Coolant Pump Seal Injection Supply Flow Control Valves (CHE-FV241, 242, 243 and 244) as containment IA header pressure drops below 26 psig?
A. Fail fully closed.
B. Fail as-is.
C. Fail fully open.
D. No response, they are motor operated.
Answer: C
Following a complete Loss of All Instrument Air (without IA system backup Nitrogen), which one of the following conditions describes the final status of the Steam Generator #1 Feedwater Economizer Isolation Valve (SGA-UV-174) with NO operator action?
A. Fails AS-IS.
B. Fails fully OPEN.
C. Fails fully SHUT.
D. Modulates on FWCS demand.
Answer: A
Assume that all digital feedwater control system control input transmitters are in service and selected to AVERAGE. The plant is at 15.5% power. Power is slowly increasing. Steam Generator #1 downcomer valve position is 80% and is opening slowly. Steam Generator #2 downcomer valve position is 70% and is opening slowly. Concerning the digital feedwater control system, which (if any) of the following automatic actions will occur?
A. Both Steam Generator #1 and Steam Generator #2 will go through swapover.
B. Only Steam Generator #1 will go through swapover.
C. No DFWCS automatic action will occur until 16.5% power is reached.
D. No DFWCS automatic action will occur until both Steam Generator downcomer valves are 80% open.
Answer: A
Instrument air header pressure is 65 psig. The reactor has been manually tripped from 100% power due to plant instability. Which one of the following describes the status of the ADV’s?
A. Have accumulators that will allow up to 13.3 hours of operation following loss of IA.
B. Will fail closed if instrument air pressure decreases to less than 60 psig and cannot be reopened.
C. Can only be operated at the remote shutdown panel upon loss of IA.
D. Can only be operated manually per 4OOP-9OP01 upon loss of IA.
Answer: A
The reactor is at 100% power. All instrument air compressors are running. IA header pressure is 88 psig and gradually decreasing. Which one of the following states when the reactor should be tripped and the Emergency Operation procedures implemented according to 40AO-9ZZ06,”LOSS OF INSTRUMENT AIR”?
A. If instrument air pressure can not be maintained above 73.5 psig.
B. If instrument air pressure can not be regained before the plant exhibits unstable operations.
C. If instrument air pressure can not be maintained above 85 psig with the Nitrogen Backup Valve open.
D. If instrument air pressure decreases to 65 psig and the Front Standard Turbine Trip Air Relay Dump Valve actuates its low pressure switches.
Answer: B
