Rad Monitoring Flashcards
What is the purpose of rad monitoring system?
Servew to warn plant personnel of rising radiation levels in various plant areas.
Each typical analog ARM RIA has the following controls and indications:
Two-scale analog meter
Nine-position function selector switch
Alarm, alert, and reset lamps/pushbuttons
Each typical analog ARM RIA has a two scale meter that indicates what?
Two-scale analog meter – provides measured radiation field indication
- Red scale spans eight decades, from 10-1 mR/hr to 107 mR/hr
- Black scale spans three decades with selectable range
- Specific range is selected using the function selector switch.
Each typical analog ARM RIA has Nine-position function selector switch that does what?
Nine-position function selector switch
“OFF” – removes power from analog meter and detector, but not from alarm lamps
- Causes channel failure and initiates channel failure annunciator
- Does not cause a high radiation alarm for the affected channel
“ALL” – output signal is scaled for red scale
- 10-1 mR/hr to 107 mR/hr
The following positions are read on the black scale:
- “107” – scales output signal to indicate from 104 mR/hr to 107
- “106” – scales output signal to indicate from 103 mR/hr to 106
- “105” – scales output signal to indicate from 102 mR/hr to 105
- “104” – scales output signal to indicate from 10 mR/hr to 104
- “103” – scales output signal to indicate from 1 mR/hr to 103 mR/hr
- “102” – scales output signal to indicate from 10-1 mR/hr to 102 mR/hr
“CS” – unshields a local check source at the detector; meter indicates on the “102“ black scale
Each typical analog ARM RIA has three push buttons that do what?
High Alarm (Red)
- Lamp lit high alarm setpoint met and/or exceeded.
- Pressing the lamp pushbutton indicates the setpoint on the analog meter.
- Generally set two to ten times normal background for that area
Alert Alarm (Yellow)
- Not connected; has no function
- Pressing the lamp pushbutton brings in circuit failure alarm
Reset (Green)
- When lit it indicates power available and reading > 10-1 mR/hr
- Resets the high alarm if level has dropped below the high setpoint. Otherwise it will alarm again.
What are Containment Gamma Monitors – RIA 2321/2322?
Containment Gamma Monitors – RIA 2321/2322
Also known as the Containment High Range Radiation Monitors
Different from the typical Analog RIA
- Two-scale analog meter (same as typical)
- Eight-position function selector switch
- Alarm, safe/reset, and test lamps/pushbuttons
Containment Gamma Monitors – RIA 2321/2322 buttons function to do what?
High Alarm (Red)
- Lamp lit high alarm setpoint met and/or exceeded.
- Pressing the lamp pushbutton indicates the setpoint on the analog meter.
- 400R/hr
Alert Alarm (Yellow)
- Lamp lit high alarm setpoint met and/or exceeded.
- Pressing the lamp pushbutton indicates the setpoint on the analog meter.
- 40R/hr
Safe/Reset (Green)
- When lit it indicates power available and reading > 1 R/hr
- Resets the alert and high alarm if level has dropped below the high setpoint. Otherwise it will alarm again.
- Indicates last self-check was completed SAT
Channel Test (Blue)
- Only functions if selector switch is in Test
Containment Gamma Monitors – RIA 2321/2322 Channel Test “Blue” button does what?
Containment Gamma Monitors – RIA 2321/2322 Channel Test “Blue” button
With selctor switch in “TEST”
Pressing and holding the blue “Channel Test” button causes
- Alert, High, and Channel Test lamps immediately illuminate
- Brings in EK-0225 [0226], “CONT GAMMA RIA‑2321 [RIA-2322] FAIL”
Release the button
- High and Alert lamps should extinguish
- Green safe lamp will extinguish only if the local radiation field is less than 1 R/hr.
Containment Gamma Monitors – RIA 2321/2322 self test?
Containment Gamma Monitors – RIA 2321/2322 self test
Every 17.1 minutes, each Containment Gamma Monitor undergoes an automatically initiated self-test using an internal electronic check source (ECS).
Also initiated with selector switch in test and pushing “ECS Test Button”
Test last six seconds.
Output signal on the analog meter rises as the self-test progresses
What are the Containment Radiation Monitors RIA-1805/1806/1807/1808.?
Analog meters but slightly different from typical analog RIA.
Each of the four has:
Analog meter
- Vertical, single-scale meter
- Only spans six decades, from 10-2 to 104 R/hr
Three-position function selector switch
- “CHECK” – Places monitor in tripped condition (Trip 2) and initiates internal self-check
- applies a voltage to the channel circuitry that corresponds to 103 R/hr, which trips the channel
- Function selector switch spring returns to “OPERATE” from “Check”
- “OPERATE” – Places monitor in service
- “TRIP ADJ” – Causes the channel output to go full-scale high
Trip 1, Trip 2, and Operate lamps/pushbuttons
RIA-1805/1806/1807/1808 Trip 1, Trip 2, and Operate lamps/pushbuttons do what?
Containment Radiation Monitors RIA-1805/1806/1807/1808 lamps/pushbuttons:
Operate (Green)
- Lit = monitor is in service.
- Not lit = may have failed low
Trip 1 (Alert – Yellow)
- Lit - met or exceeded alert setpoint of 1 R/hr
Trip 2 (High – Red)
- Lit - met or exceeded alert setpoint of 10 R/hr
- Trip 2 bistable feeds the 2 of 4 Containment High Radiation Logic
What are Containment Refueling Monitors RIA-2316/2317?
Containment Refueling Monitors RIA-2316/2317
- Energized and calibrated prior to starting core alterations.
- Removed and stored after.
- Provide inputs to the Containment Isolation logic during refueling operations
- Each monitor has a key switch located on the back of Panel C-11.
- Key switch is in the “IN” position, the associated monitor inputs to a 1/2 high alarm logic to initiate containment isolation.
- Setpoint is 80 mR/hr above background.
What are the controls/indications for the typical Digital ARM Channel?
Typical Digital ARM Channel
On-Off pushbutton
- Simply turns on/off - there are alarms
Large green LED digital display
- Displays is in scientific notation X.XXEN
- “EEEEE” displayed along with Range light lit if High out of range
- “0.00E0” displayed along with Range light lit if low out of range
Horizontal LED bar graph
- No alarm state - indication is in Green
- Warn alarm state - indication is Amber
- High alarm state - indication is Red
Four function pushbuttons
Four alarm LEDs
What is the function of the pushbutton controls for the typical Digital ARM Channel?
Typical Digital Area Radiation Monitor Pushbutton Controls
HIGH
- Press to display high alarm setpoint
WARN
- Press to display warn alarm setpoint
ALARM ACK
- Press to clear the alarm, if below setpoint
- Functions the same as the Reset button on an analog ratemeter
CHECK SOURCE
- Opens window/moves slug to expose detecting element to source.
What are the digital area radiation monitor alarm lights?
Digital AR Alarm Lights
High
Warn
Fail
- Illuminates when the ratemeter circuitry senses a channel failure
- Five minutes of zero counts from the channel detector
- Accompanied by an error code displayed on the digital display in the format, “EXXXX,” where the Xs are numerals.
- Error codes should be recorded and reported to I&C on a Work Request.
Range
- Illuminates when the measured radiation field is either out-of-range high or out-of-range low.
The CHR signal does what?
Initiated by 2 of 4 on RIA-1805, 1806, 1807, 1808
Initiated by 1 of 2 on RIA-2316, 2317
- Actuates Containment Isolation
- Trips Air Room Purge Fan V-46.
- Actuates Control Room HVAC Emergency System (Trains A and B)
- Disables automatic operation of Safeguards Rooms Sump Pumps (P-72A, 72B, 73A, 73B)
Actuates Control Room alarm EK-1363, “CONTAINMENT HI RADIATION” only when initiated by RIA-1805/1806/1807/1808.
What does RIA-5710, Penetration Fan Room Monitor, do?
RIA-5710, Penetration Fan Room Monitor
- Setpoint: 4 mR/hr
- Trips Penetration Room Supply and Exhaust Fans V-78 and V-79
- Closes dampers PO-8035 and PO-8036
What area radiation monitors provide input to the PPC?
AR Monitors that feed PPC:
- Spent Fuel Pool Criticality Monitors RIA-5709 (North) and RIA-2313 (South).
- Main Control Room Monitor RIA-2310.
- Refueling Isolation Monitors RIA-2316 and RIA-2317
- Containment Area Monitors RIA-1805, RIA-1806, RIA‑1807, and RIA-1808.
- Containment Gamma Monitors RIA-2321 and RIA-2322
If an ARM becomes inoperable what should you do?
notify Health Physics to determine if temporary radiation monitoring is needed
What brings in EK-1366, “PLANT AREA MONITORING HI RADIATION”
Any one of 26, area radiation monitors exceeding its high alarm setpoint
NOT from
- RIA-1805/1806/1807/1808 (Containment Area Monitors)
- RIA-2316/2317 (Containment Refueling Monitors)
- RIA-2321/2322 (Containment Gamma Monitors)
What is the purpose of the process radiation monitors? How many are there?
Ensures that radiation levels of process streams are indicated and alarmed so that action, either automatic or manual, can be taken to prevent radioactive releases from exceeding the limits of 10CFR20.
- 20 process radiation monitors
- Six monitors monitor liquid process streams
- Fourteen monitors monitor gaseous process streams, including area ventilation and tank vents.
- Ten monitors actuate automatic actions
What does RIA-0707, Steam Generator Blowdown Monitor, do?
RIA-0707, Steam Generator Blowdown Monitor
WARN alarm at 2000 CPM
HIGH alarm at 9.8E3 CPM
- Brings in EK‑1365, “PROCESS LIQ MONITORING HI RADIATION.”
Closes
- CV-0704, Blowdown Tank discharge to Mixing Basin
- CV-0738, “B” S/G surface blowdown
- CV-0739, “A” S/G surface blowdown
- CV-0770, “B” S/G bottom blowdown
- CV-0771, “A” S/G bottom blowdown
RIA-2320, Steam Generator Blowdown Vent Monitor
RIA-2320, Steam Generator Blowdown Vent Monitor
- RE-2320 rests in a well in the 12-inch vent header between the Steam Generator Blowdown Tank and the stack.
- Because of the high temperature environment, a continuous Service Water stream cools the detector
Automatic Actions - Closes
- CV-0704, Blowdown Tank discharge to Mixing Basin
- CV-0738, “B” S/G surface blowdown
- CV-0739, “A” S/G surface blowdown
- CV-0770, “B” S/G bottom blowdown
- CV-0771, “A” S/G bottom blowdown
RIA-0833, Service Water Monitor
RIA-0833, Service Water Monitor
Located in a detector well in the 24” Service Water return piping
No automatic actions
RIA-0915, Component Cooling Water Monitor
RIA-0915, Component Cooling Water Monitor
- WARN alarm occurs at 6000 CPM
- HIGH alarm occurs at 7000 CPM
Automatic Function
- Shifts CCW Surge Tank vent valve CV-0915 from the CCW Surge Tank room to the Gas Collection Header.
RIA-1049, Radwaste Discharge Monitor
RIA-1049, Radwaste Discharge Monitor
- When a release is in progress, RIA-1049 HIGH setpoint is set for each release at 1.5 times the calculated count rate.
- When no release is in progress, the HIGH setpoint is set at 1.5 times normal background.
HIGH alarm,
- Closes valves CV-1049 and CV-1051, thereby terminating any liquid radwaste release in progress.
RIA-1323, Circulating Water Discharge Monitor
RIA-1323, Circulating Water Discharge Monitor
Serves as a backup monitor for
- RIA-0707, Steam Generator Blowdown monitor
- RIA-0833, Service Water monitor
- RIA-0915, CCW monitor
- RIA-1049, Radwaste Discharge monitor
Low flow alarm at 1.25 GPM
NO automatic functions
RIA-5211, Turbine Building Sump Discharge Monitor
RIA-5211, Turbine Building Sump Discharge Monitor
- Full-flow in-line monitor on the common discharge header of the Turbine Building Sump pumps, P-45A and P-45B
- No automatic function
- TB sump can be aligned to dirty radwaste system
RIA-0631, Condenser Off-Gas Monitor
RIA-0631, Condenser Off-Gas Monitor
- Monitors the non-condensable gas discharge from the main condenser steam jet air ejectors on its way to the stack.
- V-6A or V-6B must be in service
- Designed to detect radioactive noble gases that would indicate a primary-to-secondary leak through a steam generator
- If a primary-to-secondary leak develops and stabilizes, setpoints will be raised so that neither the WARN or HIGH is in alarm.
- Raising after provides early indication of a change in the primary-to-secondary leak rate.
- No automatic functions
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RIA-1809, Radwaste Area Ventilation Monitor
RIA-1809, Radwaste Area Ventilation Monitor
- WARN alarm occurs at 0.7 times the selected scale
- HIGH alarm occurs at 0.9 times the selected scale
- changing the scale changes the setpoint
- HIGH alarm
- Trips Radwaste Area Supply Fan V-10
- Trips Radwaste Area Exhaust Fan selected for standby (V-14A or V-14B).
- After fans trip, closes Radwaste Area Supply Damper PO-1809 and standby fan Exhaust Damper (PO-1839 or PO-1840).
- If exhaust flow drops 25%, standby fan comes back on.
RIA-1810 and RIA-1811, East and West Engineered Safeguards Pump Room Vent Monitors
RIA-1810 and RIA-1811, East and West Engineered Safeguards Pump Room Vent Monitors
WARN at 700 cpm
HIGH at 900 cpm
Closes Engineered Safeguards Room supply damper PO-1817(1811) and exhaust damper PO-1810(1812) for affected room.
RIA-1113, Waste Gas Radiation Monitor
RIA-1113, Waste Gas Radiation Monitor
Monitors radioactive waste gas discharges from the waste gas decay tanks to the stack
HIGH alarm setpoint is variable and is calculated specifically for each waste gas release
Automatically closes waste gas discharge valves CV-1113 and CV-1123, thereby terminating the waste gas release.
RIA-1817, Containment Building Air Monitor
RIA-1817, Containment Building Air Monitor
Designed to detect high gaseous activity in the containment atmosphere, and serve as one method of detecting PCS leakage
- Sample SV (4) interlocked to V-1/2/3/4 A or B fan motors on.
- Four sample lines come together into a common 1-inch line at the radiation detector inlet.
No automatic function
RIA-5711, Radwaste Addition Vent Monitor
RIA-5711, Radwaste Addition Vent Monitor
WARN at 2000 CPM
HIGH at 1.0E4 CPM
Automatically trips Auxiliary Building ventilation fan V-67.
The exhaust fan selected for standby, V-68A or V-68B, may or may not trip
- If exhaust fan trips, its damper will close
If fan suction pressure drops to 1.5” H2O vac. With the supply fan off, the standby fan V-68A or V‑68B will start
RIA-5712, Fuel Building Addition Vent Monitor
RIA-5712, Fuel Building Addition Vent Monitor
WARN alarm occurs at 2000 CPM
HIGH alarm occurs at 1.0E4 CPM
Automatically trips Auxiliary Building ventilation fan V-69.
The exhaust fan selected for standby, V-70A or V-70B, may or may not trip
If exhaust fan trips, its damper will close
If fan suction pressure drops to 1.5” H2O vac. With the supply fan off, the standby fan V-70A or V‑70B will start
RIA-2325, 2326, and 2327, Radioactive Gas Effluent Monitoring System (RGEMS) - Normal Flow
RIA-2325, 2326, and 2327, Radioactive Gas Effluent Monitoring System (RGEMS)
Serves as a backup to all effluent streams that are discharged through the stack, such as the ventilation exhaust monitors, the gaseous waste discharge monitor, and the condenser off-gas monitor
Normal
- Sample gas flows into a particulate and iodine filter and radiation detector RE-2325.
- From there through a PDP to
- RE-2326 monitors the gas sample for radioactive noble gases
- Back to the stack
What is the RGEM Alert alarm flow?
On an ALERT condition (from RIA-2326 only), the sample gas is automatically routed to a grab-sample bomb for 15 seconds.
upstream of the RE-2325 iodine/particulate filter chamber
What is the RGEM High alarm flow?
HIGH radiation condition (from RIA-2326 only)
Routed through two flow paths.
Minor Loop Flow
- About 0.2 cfm is routed to Manual Accident Filter VF-2302.
Major Loop Flow
- About 1.8 cfm is routed through a filter assembly, from which it enters a 20-litre lead-shielded chamber that is monitored by RE-2327.
RIA-2323 and RIA-2324, Main Steam Monitors
RIA-2323 and RIA-2324, Main Steam Monitors
Monitors are designed to detect radioactive contamination in the main steam flow that would indicate a primary-to-secondary leak into a steam generator
No automatic functions
What must be done when changing the time on the RGEM purge wheel?
Shall NOT be set to 0
Any time the Accident Purge Time Thumbwheel setting on either the Remote or Local RGEM Control Panel (JIC-2301B/A) is changed the time and new setting shall be recorded in the Narrative Log
Describe the information expected to be completed on Form CH 6.23-3 (WGDT Release Authorization) prior to authorizing the WGDT release to be initiated in accordance with Form CH 6.23-3
- Tank pressure
- Release volume (m3)
- Gamma concentration of tank contents
- Expected reading on RIA-1113 during the release
- The calculated release limit for RIA-1113
- Tank isolation date and time
For a WGDT release, describe from where monitor RIA‑1113 setpoint is obtained.
RIA-1113 high alarm setpoint calculation
- Determine background count rate after RE‑113 purge
- Add background count rate to RIA-1113 Release Limit (provided by RETS Supervisor on Form CH 6.23-3).
- Sum of the two count rates is the high alarm setpoint for RIA-1113 during the waste gas release
Given plant conditions, and a WGDT release in progress, describe the necessary actions for a tripped Main Exhaust Fan in accordance with SOP-18A
Given plant conditions, and a WGDT release in progress, describe the necessary actions for a tripped Main Exhaust Fan in accordance with SOP-18A
Lower high alarm setpoint until trip
What must be done to batch a tank with RIA-1113 inoperable?
The contents of a Waste Gas Decay Tank may be released with RIA-1113 inoperable if all the following conditions are met:
- At least two independent samples of the tank contents have been analyzed prior to the release.
- At least two independent verifications of the release rate calculations have been performed
- At least two qualified Auxiliary Operators have independently verified that the WGDT discharge line-up is correct.