Aux Building, TSC and Control Room Ventilation Flashcards
Describe control room ventilation flow path.
From outside through missile barrier, dampers, roughing filter, HEPA filter, fan, heating coil, backdraft damper, humidifier.
What is the purpose of control room ventilation?
To maintain:
- Temperature within required limits. (normally 75F and 30-50% humidity)(90-95F under most adverse conditions)
- Acceptable smoke level.
- Positive Pressure following a LOCA.
What is the control room pressurization fan flow path?
Outside through snow plenum, through dampers 2 or 2A, through roughing filter, HEPA filter, Charcoal filter, through fans, backdraft damper.
Auto starts of control room pressurization system?
All 4 fans start on SI.
Hi Rad signal, and fire in that unit will start the fan in that unit
What will close Damper 3A in the control room pressurization system?
Fire in cable vault.
What does the CRAC Humidifiers use to maintain humidity?
DI water
What is the back up cooling water supply for the CRAC?
ESW.
Why do we maintain a bubble in the expansion tank on the CRAC chill water system?
With an air bubble established A small loss of water will have no functional effect on system pressure.
In what modes must the control room emergency ventilation systems be operable?
Modes 1-4
When the TSC ventilation system is in emergency mode what is realigned?
All air is aligned to go through the charcoal filters.
What is the purpose of auxiliary building ventilation?
To maintain a negative pressure in the auxiliary building to minimize the possibility of unmonitored radioactive gas release.
How do the CCW fans cool the CCW pumps?
Blow air on them
Where are the CCW fans located?
U2.
What is required to cool CCW pumps?
2 Unit 2 AS fans, or 1 U2 AS fan and 1 CCW fan, or 2CCW fans.
What must you start before you start an AS fan?
AX fan.
