Rad Monitoring and Control Flashcards
What is the purpose of the Area Radiation Monitoring System?
Consists of detectors, instrumentation, and alarms to warn plant personnel of rising radiation levels in various areas of the plant, and provides early warning of plant malfunction
What initiates a CHR signal?
2 out of 4 containment rad monitors
or
1 out of 2 containment refueling monitors
What brings in the CHR alarm in the Control Room?
Alarm is only fed by 1 out of 4 from containment rad monitors
1 out of 2 from containment refueling monitors initiates a CHR signal, but not the control room alarm
Which channel(s) are initiated by a CHR signal?
Both left and right channels are initiated regardless of which monitors cause it.
Where are area rad monitors powered from?
Preferred AC buses, or the instrument bus
What is the purpose of the interface between the Rad Monitoring System and plant ventilation systems?
Area rad monitors trip ventilation and dampers associated with that area on a high rad alarm
What is the purpose of the interface between the Rad Monitoring System and CRHVAC?
CHR initiates CRHVAC Emergency Mode
What is the setpoint for CHR signal?
10 R/hr on the containment rad monitors
80 mR/hr on the containment refuel monitors
What are the automatic actions associated with the Penetration Room Ventilation System?
High alarm at 4 mR/hr trips supply and exhaust fans/dampers to prevent the spread of radioactive noble gases and airborne particulate
What are the automatic actions associated with the blowdown rad monitor?
High alarm at 9.8E3 cpm isolates blowdown tank discharge to the mixing basin, and top/bottom blowdowns from both generators
What are the automatic actions associated with the CCW rad monitor?
High alarm at 7000 cpm re-positions CCW Surge Tank Vent from the room to the VGCH
What are the automatic actions associated with the radwaste discharge rad monitor?
High alarm at 1.5 times the calculated count rate closes both the 1” and 3” liquid radwaste discharge valves to terminate the release
What are the automatic actions associated with the radwaste area ventilation monitor?
High alarm at 900 cpm trips V-10 and V-14, and their associated dampers
What are the automatic actions associated with the ESS Rooms rad monitor?
High alarm at 900 cpm isolates supply and exhaust dampers
What are the automatic actions associated with the waste gas discharge rad monitor?
High alarm set based on decay tank contents, terminates release if high alarm setpoint is exceeded
What are the automatic actions associated with the radwaste addition ventilation monitor?
High alarm at 1.04E4 cpm trips V-67 and standby V-68, along with their associated dampers
What are the automatic actions associated with the fuel building addition ventilation monitor?
High alarm at 1.04E4 cpm trips V-69 and standby V-70, along with their associated dampers
What are the automatic actions associated with RGEM?
On an alert at 1.6E4 cpm, sample flow is routed through the sample bomb for 15 seconds to flush sample bomb and give a representative sample.
On a high alarm at 1.3E6, normal sample flow is bypassed and sample flow is diverted to accident filters and high range noble gas monitor
What is the purpose of the Process Rad Monitoring System?
Ensures that rad levels of process streams are indicated and alarmed so that action, either auto or manual, can be taken to prevent radioactive releases.
What are the consequences of improperly isolating the Waste Gas Monitor?
It can isolate the RV-1111 discharge path, thus disabling the WGST overpressure protection
What are the consequences of operating the rad monitoring system with insufficient sample flow?
Defeats the function of the monitor because it isn’t able to measure the radioactivity of a representative sample of the effluent
What information needs to be completed on a WGDT batch card?
- Tank pressure
- Release volume
- Gamma concentration of tank contents
- Expected reading on RIA-1113 during release
- Calculated release limit on RIA-1113
- Tank isolation date/time
How is the RIA-1113, Waste Gas Monitor, release setpoint obtained?
Determine the background count rate after purging the monitor, and add it to the calculated release limit on the batch card
What actions are required if a Main Exhaust Fan trips during a WGDT release?
Immediately terminate the release because you no longer have adequate dilution flow for the release
