1. CCTV System for Radiation Work Management
Yonggwang NPP Unit 5 & 6

2. Contents Ⅰ. YGN Unit 5 & 6 Ⅱ. Brief Overview of Radiation Protection
Ⅲ. Description of CCTV system
Ⅳ. Cases for use of CCTV system
Ⅴ. Effects
Ⅵ. IAEA OSART Good Practice
Ⅶ. Conclusion

3. Ⅰ. YGN Unit 5 & 6 □ Key Features Type : PWR Power Level : 1,050MWe
2 Loops, 2 S/Gs, 4 RCPs
177 Fuel Assy’s, 16 × 16 tubes
S/G : Vertical U-tube with Economizer
Condensor Heat Sink : Sea water

4. Ⅱ. Brief Overview of Radiation protection
□ Statutory Exposure Dose limit
Category
Workers
Frequent Visitors
General Public
Effective Dose Limit
100mSv per 5 years
12mSv per year
1mSv per year
□ Site Exposure Dose limit
Category
Workers
Frequent Visitors
General Public
Effective Dose Limit
16 mSv per year
10 mSv per year
1 mSv per year

5. Anticipated Exposure (man-mSv)
Ⅱ.  Brief Overview of Radiation protection [cont’d]
□ Radiation Work Control
Anticipated Exposure (man-mSv)
Counter plan
< 10
Review and check work order
10 ~ 70
Work Order Approval
70 ~ 200
ALARA Acting Level Committee Review
> 200
ALARA Committee review

6. Ⅱ. Brief Overview of Radiation protection [cont’d]
□ Collective Radiation Exposure
Year

7. Ⅲ. Description of CCTV system
□ Purpose
Radiation Exposure Reduction
Efficient Radiation Safety Control in RCA
Continuous Check-up for important works and facilities integrity
□ Characteristics
Real-time information by LAN
Movable Cameras can support important or high radiation work anywhere

8. Ⅲ. Description of CCTV system [cont’d]
□ Composition
Item
# 5
# 6
RWB
Monitoring System
1 Set -
Announcement System
Camera
Fixed
7 Sets
4 Sets
Movable
2 Sets
2 Sets
Data Cable
3.3 Km
1.1 Km

9. Ⅲ. Description of CCTV system [cont’d]
□ Network
LAN
LAN
Movable or Fixed
HP Room
Console lack
Office
Lobby Monitor

10. Ⅲ. Description of CCTV system [cont’d]
□ Location (Fixed Camera)
Building
Elevation
Location Details
Main Function
ACB
100
Locker Room Area
Prevention of robbery
Entrance to RCA
Check-up personnel coming in and out
SAB
General Access Area “ 77 ″
FHB
Truck Bay Area
Check up entry and exit of equipment and person
142
Storage Area
PAB
144
Personal Airlock Area
Controlling entry and exit in high radiation area
RWB
Hot Machine Shop
Entrance of RCA
Check-up entry and exit of equipment and person 70
Access Area

11. Ⅲ. Description of CCTV system [cont’d]
□ Location (Movable Camera)
Movable Cameras are communicated with main control center
by using connecting jack
Building
elevation
Number of jacks
Main Function
RCB
100 2
Installation and removal of SG Nozzle dam
Installation and removal of SG man-way
ECT (Eddy current test)
125
Maintenance of RCP and related works
Lancing and FOSAR in secondary side of SG
142
Reactor Maintenance
fuel loading and withdrawal
Check-up entry and exit of equipment and person

12. Ⅲ. Description of CCTV system [cont’d]
□ View of Fixed Camera

13. Ⅲ. Description of CCTV system [cont’d]
□ View of Movable Camera

14. Ⅲ. Description of CCTV system [cont’d]
□ CCTV system Diagram
HP ROOM
MONITOR
MONITOR
ACB 100’
LOCKER AREA ROOM
MATRIX
SWITCHER
MONITORING
SERVER(DVR)
ACB 100’
Entrance of RCA
11SET
SAB 100’
GEN ACCESS AREA
SAB 77’
GEN ACCESS AREA
KEYBOARD
KEYBOARD
FHB 100’
TRUCK BAY AREA
PAB 144’
4SET
LINK FACILITY
FHB 142’
STORAGE AREA
PAB 144’
PERSONAL AIRLOCK AREA
LINK FACILITY
to RWB

15. Ⅲ. Description of CCTV system [cont’d]
□ HP Room Console Rack (Main control center)
Real time Monitoring all places
where cameras are located.
Recording important works
Announcing
Auto Recording when any movement is detected.

16. Ⅲ. Description of CCTV system [cont’d]
□ Monitoring in HP Room Console Rack
All locations under surveillance
The main work place

17. Ⅲ. Description of CCTV system [cont’d] Exposure Dose (man-mSv)
Comparison (use or not)
Work
Year
Number of
workers
Working
Time (man-hr)
Exposure Dose (man-mSv)
CCTV
use or not
SG Nozzle Dam
2003 61
101
11.02
Not
2006 52 62
6.30
Use
ECT
435
1,044
38.3
290
698
23.41 SG
Man-way 83
156
6.23 81
177
4.33

18. Ⅳ. Cases for use of CCTV system
□ Removal of remaining Thermal Sleeve (T/S)
Unit 5 third Planned Outage (37 days)
<Related event description>
During the first outage of unit 5, a metal object was discovered in
the Reactor Bottom Head. (conformed by Remote Video Inspection).
As a result of the specific inspection, three metal objects were
discovered. These objects have been identified as missing thermal
sleeves from the Safety Injection Nozzle.
A remaining T/S was planned to be removed during the third Outage

19. Ⅳ. Cases for use of CCTV system
Material : Inconel 690
Size (mm) : 304(W)×554(H)×4.5(T)
Weight (kg) : 20Kg
Dose rate (removal): 6mSv/hr

20. Ⅳ. Cases for use of CCTV system [cont’d]
□ Monitoring T/S Work through CCTV System

21. Ⅳ. Cases for use of CCTV system [cont’d]
□ Result of ALARA Control
Target (mSv)
Result (mSv) %
Dose
160
73.91
53.8
Reason of exposure Reduction
Content
Reduction Rate(%)
Work control (Lead shielding and vest) 10
Reduction of the Number of person( Effect of CCTV)
Optimization of Working time (Effect of CCTV) 6
Cancellation of some work
28.8
SUM
53.8

22. Ⅳ. Cases for use of CCTV system [cont’d]
□ Effect of using CCTV System
Reduction of Exposure : 16 man-mSv (10%)
About 15 persons supervised the work through CCTV
during the working period (11days)
= persons x staying time x Radiation level in the area
Optimization of Working Time : 9.6 man-mSv (6%)
Reduction of Radioactive Waste : 1 Drum
About 220 pairs of Rubber gloves / paper protection Clothes

23. Ⅳ. Cases for use of CCTV system [cont’d]
□ Maintenance of leak Valve (SI-V522) in SI System
Date : ’ (unit 6 fourth outage)
Work Description
At the time of NOT/NOP, SI- check Valve 522 of High Presser
Safety injection Header leaked
Piping was isolated throughout Ice plugging and Valve was
Maintained
CCTV System was used to monitor the maintenance work
and ALARA Control

24. Ⅳ. Cases for use of CCTV system [cont’d]
□ Result of ALARA Control
Target (mSv)
Result (mSv) %
Dose
6.69
5.75 14
Number of workers : 16
Total working time : 6 hrs

25. Ⅴ. Effects Reduction of the number of person coming in and out
Reduction of exposure dosage
Reduction of radioactive waste
Savings in protection supplies
Real-time checkup in the office
Radiation safety control in high radiation areas

26. Ⅵ. OSART GOOD PRACTICE □ IAEA OSART Review
 Duration : ~ 5.3
 Reviewed items
- 7 items besides management, organization, &
administration sections of YGN 5&6
 Result of review in Radiation Protection Section
- 2 good practices out of 10 good practices
(No proposal for improvement)
CCTV System was evaluated as “Good Practice”
 the other is RIS (Radiation Information System)

27. Ⅵ. Conclusion Our will and endeavor should be followed
Radiation safety control is requisites for lasting
nuclear industry
Our various efforts will help to improve radiation
safety control whether it is large or not
Actually, CCTV system is small effort but the such
effort will makes a good fruit
Our will and endeavor should be followed

28. Thank You!!!

29. Maintenance of Leak Valve (SI-V522)

30. Maintenance of leak Valve (SI-V522)