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EPRI Exam Study Guide New Latest Version with All Questions from Actual Past Exam, Exams of Engineering

EPRI Exam Study Guide New Latest Version with All Questions from Actual Past Exam Updated 2024/ 2025

Typology: Exams

2023/2024

Available from 02/11/2024

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Download EPRI Exam Study Guide New Latest Version with All Questions from Actual Past Exam and more Exams Engineering in PDF only on Docsity!

EPRI Exam Study Guide New Latest Version

with All Questions from Actual Past Exam

Updated 2024/ 2025

The component of a gauge which produces the movement which allows the indication of pressure is the... --------- Correct Answer --------- bourdon tube A transmission line is rated at 1000 MVA. The power flow is currently 0 MW and 1001 MVar. Is this transmission line overloaded? (EPRI Chapter 3 , number 4) a. Yes b. No c. Cannot be determined d. The line has no load ----------- Correct Answer ---------- a. Yes The Total Transfer Capability ( TTC ) limit has been determined to be 1000 MW from east to west for a transmission path. The operator sells 500 MW on this path. What is this path's Available Transfer Capability (ATC)? (EPRI Chapter 3 , number 5) a. 1000 MW b. 1500 MW c. 0 MW d. 500 MW ----------- Correct Answer ---------- d. 500 MW An absolute pressure gauge that has been properly calibrated at sea level will read ____________at an elevation of 5000 feet. --------- Correct Answer --------- 12.23 psi A primary standard used for the measurement of pressure would be... --------- Correct Answer --------- A manometer What magnitude of frequency change would cause a 5 % droop generator to move its generator from zero to full output in a 60.00 Hz system? (EPRI Chapter 4 , similar to number 13) a. 10 Hz b. 6 Hz c. 5 Hz d. 3 Hz ----------- Correct Answer ---------- d. 3 Hz What is the MVar production of a 50 MVar shunt capacitor that is energized at 90 % of its nominal voltage?

(EPRI Chapter 5 , number 1) a. 40. b. 45 c. 55. d. 61.7 ----------- Correct Answer ---------- a. 40. A 5 % change in voltage will typically lead to what change in the total load magnitude? (EPRI Chapter 5 , number 2) a. 2 % b. 3 % c. 5 % d. 10 % ----------- Correct Answer ---------- b. 3 %

  1. A transformer can be overexcited if exposed to : (EPRI Chapter 5 , similar to number 3) a. High Voltage and Low Frequency b. Zero Voltage and High Frequency c. Saturation conditions d. Surge Impedance Loading ----------- Correct Answer ---------- a. High Voltage and Low Frequency When the MVar from a transmission line's natural capacitance is equal to the MVar the line needs to support its voltage , the line is at its : (EPRI Chapter 5 , similar to number 7) a. Surge impedance loading b. Thermal limit c. Angle stability limit d. Voltage stability limit ----------- Correct Answer ---------- a. Surge impedance loading In a radial power system , the addition of shunt capacitors at the receiving end of the system will have which impact? (EPRI Chapter 6 , similar to number 9) a. Decrease the curvature of the P V curve b. Flatten the P - V curve and increase critical voltage c. Increase the curvature of the P - V curve d. Flatten the P - V curve and decrease critical voltage ----------- Correct Answer ---------- b. Flatten the P - V curve and increase critical voltage Currents that flow in the earth's surface as a result of solar or geomagnetic disturbances are called: (EPRI Chapter 9 , similar to number 6)

a. Electrojets b. Geomagnetic induced currents c. Resonance d. Transient voltages ----------- Correct Answer ---------- b. Geomagnetic induced currents The currents induced by geomagnetic disturbances enter the power system through which path? (EPRI Chapter 9 , number 7) a. Series capacitors b. Shunt capacitors c. Transformer delta windings d. Transformer grounded neutrals ----------- Correct Answer ---------- d. Transformer grounded neutrals During a GMD event , harmonic currents may trip which device? (EPRI 9-60) a. Shunt capacitors b. HVDC c. Transformers d. Generators ----------- Correct Answer ---------- a. Shunt capacitors Why is shunt capacitor tripping a problem during geomagnetic disturbance ( GMD ) activity? (EPRI Chapter 9 , similar to number 9) a. High frequency geomagnetic induced currents ( GIC ) flow into the shunt capacitor b. Geomagnetic induced currents ( GIC ) saturate transformers which creates high frequency harmonics which cause the shunt capacitors to trip c. Geomagnetic induced currents ( GIC ) enter the power system through grounded neutrals of the shunt capacitors d. Shunt capacitors trip from high ESP ----------- Correct Answer ---------- b. Geomagnetic induced currents ( GIC ) saturate transformers which creates high frequency harmonics which cause the shunt capacitors to trip Why are high transmission system voltages problems more likely than low transmission system voltage problems during the initial stages of restoration? (EPRI Chapter 11 , similar to number 1) a. Excessive MVar supply from too many on-line generators b. Too much reactive power load c. Too much real power load

d. Excessive MVar supply from the energization of transmission lines ----------- Correct Answer ---------- d. Excessive MVar supply from the energization of transmission lines Early stages of system restoration with a frequency of 59.0 Hz The System Operator want to restore frequency to 60.0 Hz. What action should the System Operator take? (EPRI Chapter 11 , similar to number 7) a. Re - dispatch generation b. Re - configure the transmission system c. Shed 6 to 10 % of the connected load d. Shed 3 to 5 % of connected load ----------- Correct Answer ---------- c. Shed 6 to 10 % of the connected load You are in power system restoration mode , 500 MW of generation is synchronized with 300 MW of spinning reserve available. What is the largest load block that should be restored to maintain acceptable frequency control ?(EPRI Chapter 11, similar to number

a. 150 MW b. 50 MW c. 25 MW d. 10 MW ----------- Correct Answer ---------- c. 25 MW When is HVDC used? (EPRI 10-40) a. To connect two AC systems that operate at different frequencies b. Interconnect systems that operate asynchronously c. Transmission system losses are lower than AC transmission d. All of the above ----------- Correct Answer ---------- d. All of the above The simplest electrical temperature measurement device is a --------- Correct Answer --- ------ thermocouple The manipulated variable is the part of the process that is adjusted to close the gap between the set point and the value of the _____________ variable --------- Correct Answer --------- controlled To re-write the configuration information contained in a smart transmitter's EEPROM the ________________ command must be activated on the HART communicator. --------- Correct Answer --------- SEND On the Kelvin scale the freezing point of water is ... --------- Correct Answer --------- 273.15 deg. K

A temperature transmitter that has a range of - 100 to +450 degrees F. What will be the output of the transmitter if the input is 137 degrees F? --------- Correct Answer --------- 237/550=.4309(16)+4=10.89mA A pressure switch, PSL1022, which has been calibrated with a set point of 14 psi has its normally closed contact connected in series with 120volt AC circuit. If the voltage measures across the contact is 0 volts it would be a an indication that the pressure applied to the switch is... --------- Correct Answer --------- Below 14 psi The simplest device for measuring pressure is the... --------- Correct Answer --------- Manometer A relay with 2 sets of contacts would be designated with the letters... --------- Correct Answer --------- DPST Atransmitter which produces an output of 4-20mA for an input of 75-275 degrees F would have a gain of... --------- Correct Answer --------- .08mA/uf What is the value of a resistor that is color coded, yellow - orange - oragne - silver? ------ --- Correct Answer --------- 43000ohms +/-10% An advantage to using a bubbler for level measuring applications would be that... --------

  • Correct Answer --------- A bubbler doesn't require either elevation or suppression to function properly. Acolumn of mercury 14.7" high wold produce a pressure of... --------- Correct Answer ---- ----- 7.22psi The number 77 in octal is equal to __________ in decimal. --------- Correct Answer ------ --- 63 The voltage drop in a conductor is proportional to.... --------- Correct Answer --------- circuit length A gauge used in a highly dynamic process may require the use of a ___________ to limit damage to the gauge. --------- Correct Answer --------- restrictor A device which is used to indicate the mechanical position of an actuator would be identified with the letters... --------- Correct Answer --------- ZIT Calibration equipment must be __________________ in order to be used to calibrate process instruments. --------- Correct Answer --------- more accurate than the instruments to be calibrated and periodically recalibrated

The temperature of a transmitter is 20-300 degrees F. The output signal is 3-15 psig. What would be the expected output signal for an input temperature of 175 degrees F? -- ------- Correct Answer --------- 195/320=.609(16)+3=9.64 psig Most flow measurements occur under __________________ conditions. --------- Correct Answer --------- turbulent Six cubic feet of a liquid is 400 pounds. the Specific Gravity of the liquid is... --------- Correct Answer --------- 400/(62.4306=374.58) = 1. Full compensation of a remote reading thermometer would typically be provided by... --- ------ Correct Answer --------- secondary capillary An increase in viscosity of a liquid will result in a ________ Reynolds number --------- Correct Answer --------- lower A tank contains 9 cubic feet of a liquid. The liquid weighs 470 pounds. The specific gravity of the liquid is... --------- Correct Answer --------- 470/(62.439=561.87)=.836inwc In most process control systems the process measurement is derived from a... --------- Correct Answer --------- sensor A type of OPEN CHANNEL flow meter which is typically used to measure WATER flow is the ... --------- Correct Answer --------- Parshall Flume when using a voltmeter without a reference junction to measure the out put of a thermocoulple it is necessary to... --------- Correct Answer --------- Subtract the reference junction millivolts from the instruments voltage reading A type of level transmitter which would require that the vessel containing the liquid was open to the atmosphere would be a... --------- Correct Answer --------- bubbler A bubbler has the following instruments connected as part of the control loop; FI1001, PCV1001, LIT1001, LIC1001. Which device would most commonly be used for the flow indicator? --------- Correct Answer --------- Rotameter The most common unit of measure for liquid pressure or level is... --------- Correct Answer --------- inches of water The temperature at which the moisture in the air will become saturated and begin to be deposited as condensation is... --------- Correct Answer --------- Dew Point a circuit having the resistance of 100 ohms and an applied voltage of 48 volts will consume ____________ of power. --------- Correct Answer --------- 48/100=.48(48)=23.04watts

When checking the calibration of a differential pressure transmitter you find that it renders readings at the 25%, 50%, and 75% test points which are substantially higher than anticipated. This would indicate that the instrument probably has... --------- Correct Answer --------- Square root extraction the symbol "TE1002" would most likely represent a... --------- Correct Answer --------- Thermocouple Loss of signal from a compensation lead of a smart temperature transmitter with a three wire RTD will usually cause an output condition which will be... --------- Correct Answer - -------- Dependent upon the setting of the failure mode. Temporary information storage is usually done in --------- Correct Answer --------- RAM A DC milivlt signal could be used to provide anINPUT to a(n) __________ transmitter --- ------ Correct Answer --------- PH The differential pressure produced across an orifice plate will be proportional to... --------

  • Correct Answer --------- The square of the percentage of maximum flow rate A customer is fed at 120 volts. The customer voltage is doubled while the load magnitude stays the same. What effect does this have on the power losses? (EPRI Chapter 2, number 4) a. Doubles the losses b. Halves the losses c. Increases the losses by a factor of four d. Decreases the losses by a factor of four ----------- Correct Answer ---------- d. Decreases the losses by a factor of four The actual voltage is 362 kV on a 345 kV bus. What is the per unit (p.u.) voltage? (EPRI Chapter 2, number 6) a. 1. b. 1. c. 1. d. 0.95 ----------- Correct Answer ---------- b. 1. A load has a power factor of 0.9 lagging. If the load draws 100 MVA , what is the MW draw? (EPRI Chapter 2 , number 7) a. 100 b. 90 c. 111 d. 44 ----------- Correct Answer ---------- b. 90

200 MW is scheduled to flow from Bus " X " to Bus " Y ". Transmission line " A - B " has a 10 % distribution factor for this schedule. How much of the 200 MW schedul will flow on transmission line A-B (EPRI Chapter 3 , number 10) a. 20 MW b. 40 MW c. 180 MW d. 200 MW ----------- Correct Answer ---------- a. 20 MW According to the load / frequency relationship , a 1 % change in frequency will lead to what approximate magnitude of load change in a typical 10,000 MW system? (EPRI Chapter 4 , number 1) a. 500 MW b. 1000 MW c. 200 MW d. 50 MW ----------- Correct Answer ---------- c. 200 MW A governor with a 0 % droop is called: (EPRI Chapter 4 , number 2) a. Flat frequency control b. Transient droop c. A blocked governor d. An isochronous governor ----------- Correct Answer ---------- d. An isochronous governor A Balancing Authority's frequency bias setting is equal to EPRI Chapter 4 , number 4 ) a. The control area's frequency response characteristics ( FRC ) b. The natural response of the balancing area c. The AGC system's bias value d. All of the above ----------- Correct Answer ---------- d. All of the above

  1. A Balancing Authority has a bias of - 150 MW / 0.1 Hz. Frequency falls 0.05 Hz due to an external disturbance. How many MW would you expect this Balancing Authority to provide? (EPRI Chapter 4 , number 8) a. - 75 MW b. +75 MW c. - 150 MW d. +150 MW ----------- Correct Answer ---------- b. +75 MW

Phase Shifting Transformers are used for what? (EPRI 10-40) a. Tool for controlling the flow of MW b. Control impedance c. To consume MVAR from the system d. Control voltage level ----------- Correct Answer ---------- a. Tool for controlling the flow of MW What is the primary safety concern for nuclear power plant operations? ---------- Correct Answer --------- Preventing significant radiation exposure to the public during routine and accident conditions. How is the primary safety concern for nuclear power plant operations achieved? ---------- Correct Answer --------- Employing fission product barriers and engineered safety features. Identify ways a core can fail ---------- Correct Answer --------- Any loss of core geometry, particularly into a configuration where cooling becomes impractical, is considered a core failure List three ways that the core has an inability to fully remove the heat created by the fuel ---------- Correct Answer --------- 1. A failure of the heat removal systems

  1. An increase of heat created beyond the ability of the heat removal systems
  2. The inability to transfer heat from the fuel What are the three fission product barriers? ---------- Correct Answer --------- 1. fuel pellet and cladding
  3. Reactor Coolant System (RCS) pressure boundary
  4. Containment Prevents the escape of fission products from cladding ---------- Correct Answer --------- Fuel pellet and cladding (first fission product barrier) Contains the radionuclides that escaped the cladding or were produced outside the cladding ---------- Correct Answer --------- RCS pressure boundary (second fission product barrier) Holds radionuclides that have escaped from the RCS ---------- Correct Answer --------- Containment (third fission product barrier) The defense-in-depth policy states that a utility should: ---------- Correct Answer ---------
  5. Design to prevent the occurrence of nuclear accidents
  6. Assume that accidents will occur
  7. Provide proven capability to meet the range of worst-case accidents

Defined as hypothesized events that affect one or more of the radioactive material barriers and that are not expected during plant operations ---------- Correct Answer ------- -- Accidents What are two accident types that are considered? ---------- Correct Answer --------- 1. Mechanical failure of a single component leading to the release of radioactive material from one or more barriers

  1. Arbitrary rupture of any single pipe up to and including complete severance of the largest pipe in the nuclear system process barrier By definition, what is typically a worst-case accident of interest ---------- Correct Answer - -------- Design Basis Accident (DBA) When designing a plant, the philosophy documented in the FSAR contains several layers. Which of the following assumptions are used to ensure core protection? ---------- Correct Answer --------- a. The plant is operating in a given band via proper control b. The plant is assumed to be in steady state prior to the transient c. The plant is being operated within Technical Specifications A design basis accident is typically a worst-case accident of interest.... T/F ---------- Correct Answer --------- True
    • It is the specification to which a plant is designed Primary safety concern for nuclear power plant operation is.... ---------- Correct Answer -- ------- the protection of the public from the release of fission products First line of defense is.... ---------- Correct Answer --------- keeping the core covered, cooled, and properly reactive The systems of the plant are designed with several layers of protection including.... ------ ---- Correct Answer --------- automatic controls, alarms, and automatic protective systems. The focus of accident mitigation is.... ---------- Correct Answer --------- protecting the reactor core is a quantitative assessment of the risk associated with plant operation and maintenance ---------- Correct Answer --------- Probabilistic Risk Assessment (PRA) Also known as Probabilistic Safety Assessment (PSA) What is the original goal of PRA? ---------- Correct Answer --------- To analyze and understand sever accident behavior, and then identify and fix the plant vulnerabilities What are the attributes of a PRA ---------- Correct Answer --------- 1. It realistically models plant design, plant procedures, and human performance
  2. It is a best estimate
  1. It is not a safety-related tool
  2. It is a mathematical model of all important plant systems using plant - specific data for critical components
  3. It models the plant response for various initiating events using calculated systems reliabilities
  4. It takes into account realistically usable mitigating equipment Several conservative (worst-case) assumptions are used to set the bounds for the design... ---------- Correct Answer --------- - Worst case single failure of equipment
  • Non-safety equipment not available during an accident
  • Equipment providing no capability if not fully operable Baseline for plant configuration to mitigate the various design basis events. ---------- Correct Answer --------- Technical Specification's Limiting Condition for Operation (LCO)
  • Used in design and licensing
  • YES or NO answer
  • Uses conservative techniques
  • Evaluated worst case single failure
  • Assumes non-safety related equipment is not available
  • Adverse consequences is typically defined as cladding damage
  • Operable ---------- Correct Answer --------- Deterministic Analyses
  • Used in licensing
  • Estimated the likelihood of the YES/NO answer
  • Uses realistic techniques
  • Considers the Probability of a Failure
  • Considers Multiple Failures
  • Credits all potentially available equipment. Any possible plant configuration may be included
  • Adverse consequences defined as Core Damage that is generally taken as loss of structural integrity of the fuel
  • Functional ---------- Correct Answer --------- Probabilistic Analyses A key difference between deterministic analysis and PRA is.... ---------- Correct Answer - -------- deterministic analysis is based on conservative assumptions, while PRA uses realistic analyses based on all available methods and equipment What ranks components and systems in their order of risk/importance to the plant -------- -- Correct Answer --------- PRA Models What is a tool used to evaluate risk / safety significance and is useful when making decisions regarding plant operation? ---------- Correct Answer --------- PRA Uses PRA when:
  • Installing new safety-related equipment to the plant
  • Adding a backup cooling supply to a piece of safety-related equipment
  • Changing control room indications
  • Replacing an AOV with an MOV
  • Changing failure mode of equipment ---------- Correct Answer --------- Design Engineers Use PRA when:
  • Supporting justifications for continued operation
  • Incorporating Maintenance Rule (10CFR50.65)
  • Using the Mitigating Systems Performance Index (MSPI)
  • Determining risk factors for on-line work activities
  • Providing input for plant testing ---------- Correct Answer --------- Systems Engineers Use PRA when:
  • Using the Significance Determination Process
  • Using the Mitigating Systems Performance Index (MSPI)
  • Using the Regulatory Oversight Process
  • Providing basis for Equipment out of Service (EOOS)
  • Providing basis for risk-informed Technical Specifications ---------- Correct Answer ------ --- Licensing / PRA Engineers Plant modifications have no affect on plant's CDF.... T/F? ---------- Correct Answer --------
  • False. Any plant modification can have an effect on plant's CDF. For instance, adding an additional power source to mitigate the loss of off-site power can greatly reduce the chance that a core damage event will occur at the power plant. What type of engineer use PRA when installing new safety--related equipment? ---------- Correct Answer --------- Design Engineer What type of engineer use PRA when providing basis for risk-informed Technical Specifications? ---------- Correct Answer --------- Licensing / PRA Engineer What type of engineer use PRA when Incorporating Maintenance Rule? ---------- Correct Answer --------- Systems Engineer limits on the specific nuclear process variables imposed by technical specifications. These limits are set to ensure the integrity of the fission product barriers ---------- Correct Answer --------- Safety Limits These specify the minimum acceptable levels of system performance necessary to assure safe operation of the facility. ---------- Correct Answer --------- Limiting Conditions of Operation (LCOs) State the hierarchy of limits on safety parameters ---------- Correct Answer --------- Normal Automatic Controls Alarms / Operator Action Automatic Trips / Relief

Emergency Operating Procedure / Operator Action Tech Spec Limit Design / Test Limit Break Point List some safety limits for a BWR: ---------- Correct Answer --------- - Maintain thermal power less than some maximum Reactor Thermal Power (RTP) with low reactor coolant system pressure and low core flow.

  • Minimum Critical Power Ration (MCPR) greater than some mnimum limit with higher reactor coolant system pressure and core flows above some minimum value
  • Reactor water level greater than the top of active irradiated fuel
  • Reactor steam dome pressure less than a maximum limit List some safety limits for a PWR: ---------- Correct Answer --------- - Fuel pin centerline temp less than some maximum limit
  • Departure from Nucleate Boiling Ratio (DNBR) greater than some minimum value
  • RCS pressure less than some maximum value List the four major sections of an LCO ---------- Correct Answer --------- statement applicability actions surveillance requirements Safety limits are established to: ---------- Correct Answer --------- Ensure the integrity of the fission product barriers When the minimum conditions for operability are not met for a LCO, which section of the LCO informs the operator of actions to take? ---------- Correct Answer --------- Action Statement Most plant parameters have controls that should be keep them within established set points - Is what layer of protection for the safety significant parameters? ---------- Correct Answer --------- Normal automatic controls Alarms are typically initiated to let the operator know when a parameter has deviated from where it should be maintained by the automatic controls. This will allow the operators to take action before the trip or relief setpoint is reached. those actions will be guided by procedures such as normal operating procedures, alarm response procedures, and abnormal operating procedures - Is what layer of protection for the safety significant parameters? ---------- Correct Answer --------- Alarms / operator action If safety significant parameters deviate too far from normal, the equipment can take two actions to protect itself. in the case of over temperature, voltage, pressure, etc. the equipment can automatically trip to stop the addition of more energy. In the case of pressure, the equipment can additionally relieve the energy through the use of relief valves. It is possible for the equipment to be designed to either relieve or trip first. Then

if the condition doesn't improve, it could perform the other. ---------- Correct Answer ------ --- Automatic trips / relief The operators are scanning the safety significant parameters to make sure they are not moving too far out of the setpoints without action being taken. If the parameters asses the point where and automatic trip or relief should have taken place, operating procedures will have the operators take action. ---------- Correct Answer --------- Emergency operating procedures / Operator action All alarms or actions taken before this point should prevent the equipment from reaching the tech spec limit. The plant is analyzed to survive a design basis accident with the parameter less than that value. This is the plant's licensing basis. ---------- Correct Answer --------- Tech Spec Limit This is the highest value fro a specified parameter that a piece of equipment is designed to survive and remain operational. In some cases, this is the value where the equipment was tested ---------- Correct Answer --------- Design/ Test Limit The point where the equipment actually fails is somewhere above the design limit. There is no way to know this value without an actual failure ---------- Correct Answer ----- ---- Break point In a pressurized water reactor, the core is cooled while at power by which of the following mechanisms? ---------- Correct Answer --------- Thermal energy from the fuel is transferred to the reactor coolant that then flows out of the reactor vessel to the steam generator, where the thermal energy is used to produce steam. In a boiling water reactor, the core is cooled while at power by which one of the following mechanisms? ---------- Correct Answer --------- Thermal energy from the fuel is transferred to the reactor coolant to produce steam in the reactor vessel. What system in a PWR is normally used immediately after a unit shutdown to remove decay heat? ---------- Correct Answer --------- Reactor Coolant System, Natural Circulation Which of the following are other options to remove decay heat when primary fluid temperatures are too low to support adequate steam formation in the steam generators? ---------- Correct Answer --------- Residual Heat Removal System What four conditions must be present for natural circulation to occur? ---------- Correct Answer --------- 1. A heat source (the reactor core)

  1. A heat sink to which the secondary fluid transfers its heat (the steam generators)
  2. The heat sink (steam generators) must be at a higher elevation than the heat source (reactor core)
  3. A continuous, unobstructed flowpath (the reactor coolant system piping)

Which of the following is an indication that natural circulation is occurring? ---------- Correct Answer --------- A RCS core exit thermocouple temperatures are stable or decreasing Method for injecting large amounts of makeup water into the reactor core during accident / emergency conditions, when the normal method of core heat removal is insufficient or unavailable ---------- Correct Answer --------- Safety Injection (SI) List the four Emergency Core Cooling Systems in a BWR ---------- Correct Answer ------- -- - High pressure core spray

  • High pressure coolant injection
  • Low pressure coolant injection
  • core spray or low pressure core spray
  • Automatic depressurization system Used to restore and maintain the reactor pressure vessel water level after a LOCA event where the reactor vessel has been depressurized. this system is part of the residual heat removal (RHR) ---------- Correct Answer --------- Low Pressure Coolant Injection (LPCI) typically worst-case accident of interest used to design plant components ---------- Correct Answer --------- Design Basis Accident (DBA) What are PWR Indications of a DBA? ---------- Correct Answer --------- - Unusual increase in containment pressure
  • Decreased reactor coolant system pressure
  • All ECCS pump start
  • Reactor may empty and depressurize What are BWR indications of a DBA? ---------- Correct Answer --------- - Rapid rise in dry well (primary containment) pressure
  • Decrease in reactor water level
  • All ECCS pumps start
  • Reactor empty and depressurized (inventory to suppression pool) What is the most prevalent hydrogen source after a design basis LOCA (chronic source of hydrogen)? ---------- Correct Answer --------- Radiolytic Decomposition of Water What are the four critical safety functions that protect the fuel pellet and cladding? ------- --- Correct Answer --------- Sub-criticality, core cooling, heat sink, and RCS inventory What four critical safety functions that protect the RCS pressure boundary? ---------- Correct Answer --------- Sub-criticality, heat sink, RCS integrity, RCS inventory What critical safety function protects the containment barrier? ---------- Correct Answer -- ------- Containment Integrity.

Identify the critical parameters monitored during accident conditions in a PWR ---------- Correct Answer --------- - RCS Wide range Thot & Tcold Temperatures

  • RCS pressure
  • Pressurizer (PZR) Water level
  • Steam Line Pressure
  • Steam Generator (SG) Water level
  • Containment Pressure
  • Refueling water storage tank level
  • Reactor vessel levels indicating system (RVLIS)
  • Core Exit Thermocouples Temperatures Identify the critical parameters monitored during accident conditions for a BWR ---------- Correct Answer --------- - Reactor vessel water level
  • Reactor vessel pressure
  • Dry well pressure and temperature
  • Suppression chamber water temperature and level
  • Source range neutron levels Potential degradation of the plant's level of safety and escalation to more serious emergencies ---------- Correct Answer --------- Notification of unusual event Actual or potential substantial degradation of the level of safety of the plant ---------- Correct Answer --------- Alert Actual or likely major failures of plant functions needed for protection of the public -------- -- Correct Answer --------- Site area emergency Actual or imminent substantial core degradation or melting with potential for loss of containment integrity. ---------- Correct Answer --------- General Emergency Requires that reactor coolant and containment samples be obtained and analyzed within hours after an accident. Requires that these instruments be ranged for the worst anticipated accident and that they be environmentally qualified to withstand the heat, humidity, and pressure of the post-LOCA containment atmosphere. ---------- Correct Answer --------- US NUREG 0737