Fire Protection Flashcards
What functions does the fire protection program provide IAW 10CFR50 APP R?
1) Establishes fire protection policy
2) Have a fire hazards analysis which shall be performed by fire protection and reactor engineers
3) Have fire prevention features
4) Where protection features cannot ensure safe S/D capability due to fire, alternative or dedicated safe S/D capability shall be provided
What Nuclear safety performance criteria are required by NFPA 805?
A) Reactivity Control
B) Inventory and Pressure Control
C) DH Removal
D) Vital Auxiliaries
E) Process Monitoring
What pressures does P-11 Jockey Fire pump cycle at?
Autostarts at 118# and stops at 134#. Powered from B-13.
What pressures do P-6A and P-6B start and when/where can they be secured?
P-6A autostarts at 110# and can be secured locally or in CR > 120#.
P-6B autostarts at 90# and can be secured locally only when > 100#.
What are admin/alarm and TRM requirements for T-29 level?
Admin - 30”
Alarm - 29”
TRM - 27”
TRM level ensures 8 hours of run time for pump.
What are the 4 types of sprinkler systems?
Wet Pipe - Have fusible links with check valve type sprinkler valves providing alarm indications
Dry Pipe - Has no water in sprinkler header with open sprinkler heads
Deluge - open sprinkler heads (no fusible links). When valve opens water flow occurs immediately through sprinkler heads and actuates alarm.
Pre-action - dry pipe systems with fusible links installed. Requires actuation along with melting fusible head for flow. Used in areas where accidental actuation would be detrimental.
What ES channels are the RB firewater isolation valves and what position are they maintained in?
2 isolation valves actuated by ES 3/4 are maintained closed during normal operation for containment penetration.
Where all does Halon actuate in the CR and how is it actuated?
Halon has 3 different systems: Aux CR floor, aux CR ceiling and main CR ceiling.
Halon is actuated by 2 smoke alarms in CR. Upon actuation, a solenoid valve opens allowing N2 pressure to open pilot cylinder. Halon pressure from pilot cylinder opens the slave cylinders.
Low pressure alarm is at 300 psig.
Can be actuated manually locally or from C463.
Why is Halon used rather than C02?
Halon is used instead of CO2 due to the inaccessibility of the protected areas and the around-the-clock manning requirements of the Control Room. Halon is faster acting than C02 and is not absorbed by the blood as rapidly as CO2.
Where all is cardox supplied to?
Main turbine bearings, Exciter and U2 Exciter
What actuates cardox and how long will it supply the bearings?
Bearings 1 - 3 actuate at 195 F, 4 & 5 actuate at 325 F.
Will supply turbine bearings for 3.5 minutes, 20 mins to the exciter.
What are the setpoints for T-108 Cardox tank?
357# - Safety lifts
341# - Bleeder lifts
325# - High pressure alarm
305# - Refrigeration unit starts
295# - Refrigeration unit stops
275# - Low pressure alarm
How does a typical fire detector string work?
- FIU & ZIU feed C463 (power Y02) and provide indication of alarms and troubles. FIUs go to ZIUs and ZIUs communicate to C463.
- Trouble relay de-energizes indicating an issue with the detection circuit - does not mean detector actuated (open circuit)
- Fire alarm relay energizes
- The Alarm coil will then close a normally open contact to generate a fire alarm and for some suppression systems, an actuation of the sprinkler valve.
What is a cross zone system?
Cross zones have smoke and flame detectors such as EDG room.
Must have 50% to be functional (all smoke detectors or all flame detectors
Must have 1 flame and 1 smoke detector actuated for actuation
What are the different types of detectors used?
Fenwall Detectors - When air temp is high enough, contacts close the detection circuit and actuate applicable control device. When temp decreases below setpoint, contacts open and device resets. Fire hot enough could result in fusing the contacts together and inability to reset.
Flame Detectors - Detector senses infrared radiation produced by flames. Must be maintained > 5 seconds to cause alarm.
Protectowire - fire will melt insulation and short out wires causing indication to go high. Normally read 10 mA.
