Purge and Vent Flashcards
What is the purpose of the Radwaste Area HVAC System?
The Radwaste Area HVAC System supplies filtered and heated (as necessary) outside air to the radioactive waste processing areas of the Auxiliary Building and those spaces currently used by health physics personnel at Access Control.
What is the purpose of the Engineered Safeguards Room HVAC System?
The Engineered Safeguards Room HVAC System circulates cool air in the ESS Rooms under conditions of abnormally high temperature in these spaces in order to cool the ESS Rooms and contained equipment.
Supply air for each Engineered Safeguards (ESS) Rooms is provided from the Radwaste Area HVAC System to the ES Rooms via PO-1812 and 1817.
What is the purpose of the Auxiliary Building Addition Radwaste Area HVAC System?
The Auxiliary Building Addition Radwaste Area HVAC System supplies filtered and heated (as necessary) outside air to the radioactive waste processing areas of the Auxiliary Building Addition Radwaste Area.
What is the purpose of the Fuel Handling Area HVAC System?
The Fuel Handling Area HVAC System supplies filtered and heated (as necessary) outside air to the fuel pool area and adjacent spaces, in order to permit personnel access and to control airborne radioactivity in the area during normal operation.
The Fuel Handling Area HVAC System also limits site boundary radiation doses during a fuel cask drop or other fuel handling accident scenarios.
What is the purpose of the Auxiliary Building Addition Fuel Handling Area HVAC System?
The Auxiliary Building Addition Fuel Handling Area HVAC System supplies filtered and heated (as necessary) outside air to the fuel pool area and several adjacent areas at the same level and the next lower level, in order to permit personnel access and to control airborne radioactivity in the area during normal operation
What is the purpose of the Penetration and Fan Room HVAC System?
The Penetration and Fan Room HVAC System supplies filtered outside air to the area where the main feedwater and main steam piping penetrate containment.
What is the purpose of the Containment Purge System?
The Containment Purge System provides suitable ventilation to containment during shutdown conditions.
What is the purpose of the Main Exhaust System?
The Main Exhaust System provides suitable ventilation conditions for exhausting air from the Auxiliary Building and Containment HVAC Systems to the main exhaust stack (i.e., negative pressure in the exhaust plenum).
What is the general purpose of each radiologically controlled areas ventilation system?
- Provides a suitable environment for equipment and personnel.
- The airflow runs from areas of low radioactivity toward areas of progressively higher activity for ultimate discharge from the Plant via the main exhaust stack.
- The exhaust air is ducted to HEPA filters:
- to assure minimum radioactivity levels for the main exhaust stack discharge, and
- to maintain containment of radioactive particles in those areas of possible contamination
- The design exhaust flow exceeds the supply exhaust flow in order to create a negative pressure in the areas served and thus minimize the release of radioactive contamination.
What is the flowpath via major components of the Radwaste Area HVAC system?
Intake via supply fan V-10
- Inlet damper PO-3010
- pre-filter VF-10
- preheat coil VHX-10
- reheat coil VHX-13 to the suction of the fan.
Split into 2 major air supply headers
- One supplies air to offices, lockers, showers, and counting labs via heating coil VHX-38 and cooling coil VHX-52, cooled by chill water.
- The other header provides air via isolation damper PO-1809 to potentially contaminated areas that contain radwaste treatment equipment. A
- Also provides air to the ESS Rooms through dampers PO-1817 (east) and PO-1812 (west).
V-14A/B, Radwaste Area HVAC Exhausters
- Return air is exhausted to the main exhaust plenum after passing through a filter unit and then the exhast fans.
- CWRT T-64D vent path for containment purge connects at the inlet to the filter unit
- Radiation monitor RIA-1809 monitors radwaste exhaust filters inlet plenum and provides for system isolation on high radioactivity.
What interlocks are associated with V-10, Radwaste Area Supply Fan?
RIA-1809 trips V-10 on a high rad alarm
V-14A/B (one is always in standby which means running) trips with V-10
- Not needed to maintain negative pressure, unless it is only fan running.
- If airflow drops, standby fan will restart.
What is the function and location Radwaste Ventilation Radiation Monitor RIA-1809?
Radwaste Ventilation Radiation Monitor RIA-1809
Reset Pushbutton on C-13
- Located at inlet plenum to V-14A/B
- Trips V-10
- Trips closed East & North Corridor Supply Damper PO-1809
- HS on C-03
What are the controls and indications for V-10 and V-14A/B
Supply fan V-10
- CLOSE/TRIP switch (spring return to center position) on C-13.
- Freen/Red fan stopped/running lights at fan control switch
- Amber light at control switch has no function
Exhaust fans V-14A/B
- CLOSE/TRIP/ switch (spring return to center position) on C-13
- Close/Open flag at fan control switches.
- Standby fan select switch on C-13 selects either V‑14A or V-14B as the standby fan
What precautions and limitations does SOP-24 have for the Radwaste Area HVAC system?
- At least one V-14A/B fan is required to ensure adequate sampling of rad monitors and to prevent potential radiological contamination of personnel in the Chemistry sampling area using affected fume hoods.
- V-10, V-14A and B should be on if the equipment hatch is open.
- Do not remove V-10 and V-67 (Aux Bldg. Addition Radwaste Area supply fan) from service at the same time because Aux Building ventilation imbalances will result.
- V-10 and V-14A/B are stopped during V-6A/B transfer to minimize backpressure on exhaust plenum when both V-6A/B are off, which could cause reverse flow through filters and a resultant release of radioactivity (e.g., VF-66 or VF-58).
How is the Radwaste HVAC system started and stopped?
Startup
- Verify RIA-1809 in service, alarm cleared, and damper high rad isolation reset.
- One V-14A or B fan is started, then V-10 is started followed by the other V-14 fan. (Notify Chemistry prior to starting V-14A/B fans if both were off per SOP-24, 8.3.2)
- Steam heating is provided, if needed
Shutdown
- Notify Chemistry prior to stopping both V-14A & B (per SOP-24, 8.3.1).
- V-14A or B is stopped and then V-10 is stopped.
- Remaining V-14 fan is stopped.
Is the Engineered Safeguards Room HVAC safety related?
Yes.
The safety-related (Q) components in the ESS Room HVAC System are ESS Room coolers, fans, motors, controls, and ceiling mounts.
- Service water piping and control valves for ESS Room coolers.
- ESS Room isolation dampers, damper positioners, and isolation signals
V-27A/D are not safety related nor required for Tech Specs.
What is the design function of the ESG room coolers?
The ESS Room coolers are designed to limit the temperature in the ESS Rooms to 135°F during a LOCA
What supplies fresh air to the ESG rooms?
Where does it exhaust?
What closes them?
Radwaste Area HVAC system through
- PO-1817 - East Safeguards Supply Damper
- PO-1812 - West Safeguards Supply Damper
Exhaust to Radwaste Area HVAC system through.
- PO-1810 - East Safeguards Supply Damper
- PO-1811 - West Safeguards Supply Damper
RIA-1810 isolates East Safeguards Dampers
RIA-1811 isolates West Safeguards Dampers
Where and what are the damper controls for PO-1810, 1817, 1811 and 1812?
CLOSE/OPEN/OVERRIDE TO OPEN switch for PO‑1810, PO-1817 (EAST), and PO-1811, PO-1812 (West) on C-03 AND C-33
Key lock switch – one for each set of dampers
- HS-1810A for PO-1810 & 1817
- HS-1811A for PO-1811 & 1812
Red/Amber/Green indicator lights – Amber lights are lit when the associated control switch on C‑33 is NOT in remote OR when HS-1810A/1811A is in the OVERRIDE TO OPEN position
What are the power supplies to V-27A/B/C/D?
MCC-1
- V-27A - East Engineering Safeguards Cooler Fan
- V-27C - West Engineering Safeguards Cooler Fan
MCC-2
- V-27B - East Engineering Safeguards Cooler Fan
- V-27D - West Engineering Safeguards Cooler Fan
At what temperatures do the V-27 fans start and stop?
STANDBY - 90°F
AUTO - 85°F