Radiation Protection

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Radiation Protection in the Nuclear Industry at
Sellafield
Colin Partington
British Nuclear Group
UKRC June 2004
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What we do at Sellafield Organisation
Design and Targets Radiation Protection
Techniques Safety Performance
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Sellafield
Reprocess Magnox Fuel Reprocess Oxide Fuel Make
MOX Fuel Treat Radioactive Waste Watch old
Plants Decommission Plants Build new plants
12,500 radiation workers 4,000 contractors
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Achieving Quality and Safety
Design
Standards
Construction
Quality Assurance
Audit
Commission
Lesson Learning
Operation
Involvement
Openness
Maintenance
Experience
Decommission
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Ionising Radiations Regulations 1999 and
Sellafield

• Appointing people to be responsible for radiation
  safety
• Appointing Qualified Experts Radiation Protection
  Advisers
• Carrying out risk assessments
• Providing contingency plans
• Designating areas on the basis of radiation or
  contamination
• Providing Local Rules for people entering such
  areas
• Monitoring radiation exposure
• Setting dose limits for employees and members of
  the public
• Reporting radiation events and recording them

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Safety Management
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Appointing People
to be responsible for radiation safety
Radiation Protection Supervisors

• Seems obvious, but accountability is important
• The RPS must be an intelligent customer
• Done quite differently in some places.
• We believe it means the person directly
  supervising work with radiation

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Radiation Protection Advisers
IRR99 requires Radiation Employers to appoint
Suitable Radiation Protection Advisers
Radiation Protection Advisers
Certificated by an Assessing Body
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Safety Advice and Monitoring
of which
serving
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Design Policy
Average Radiation Exposure less than 5 mSv
per year Maximum Radiation Exposure less than
15 mSv per year Extremity Exposure less than
300 mSv per year Internal Exposure negligible
Plant Design subject to ALARP
As Low As Reasonably Practicable
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Operating Limits and Targets
Prior to 1957 250 mSv per year 1957 30 mSv
per Quarter (50(N-18)mSv 1977 50 mSv per
year 1986 50 mSv per year (Ext Int) 1988 30
mSv per year (Ext Int) 1990 20 mSv per year
(Ext Int) 1991 15 mSv per year (Ext Int)
150 in ten years 75 in five years
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Measuring radiation exposure
Radiation Sources Chemical Plant Mechanical
equipment Surface contamination
Film Badge Thermoluminescent Dosimeters Electronic
Dosimeters Neutron Dosimeters Area Gamma Alarms
External
Internal
Inhalation gases dusts Ingestion eating inadverten
t Direct cuts skin
Static Air Samplers personal Air Samplers Whole
Body Monitors Urine and Faecal Samples Nose
Blows Blood
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Internal Exposure prevention
Well defined contamination control boundaries
with monitoring between.
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Measuring Internal Dose
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Radiation Reduction Methods

• Involvement
• Dose Measuring
• Dose Tracking
• Dose Budgeting
• Job Analyses
• Engineering solutions
• Behavioural Safety
• Rotation/Job Sharing
• New Plant

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Engineering improvements
From open working to cell and remote working
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Typical Operation
Nitric Acid Evaporator
Reprocessing liquors
MBq /l AlphaGBq/l Beta
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Radiation Levels
Radiation Levels400 microSv/hrLong working
timesALARP Optioneering to find most
effectivesolution
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The ALARP Process
- Set Policy - Optioneering - Dose assessment -
Break into packages - Identify preparation
framework
- for each package - Review team process HAZOP -
Access/Interference/Timing - Training - Set
budgets
- Control - TV, Communication - Monitor -
Briefing and training
- To feed the next job
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Preferred Option -partial decontamination
High Pressure Jet washingChemical
decontaminationRemoval of redundant pipes and
equipment
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Outcome - Magnox Reprocessing average doses
Outcome - Collective Dose 61
man-milliSvMaximum Individual Dose 2 mSv
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Average Exposure
0 1 2 3 4 5
Reactors 4.9 Magnox Reprocessing
1.9 Thorp Reprocessing 1.2 Waste
Effluent Treatment 0.9 Decommissioning
4.3 Services 1.2 Contractors 0.9
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Stages of ALARP
Engineering Approach Shielding Ventilation Rem
ote Revised layout
Management Systems Cost Benefit
Analysis Systematic and Structured Dose
Budgeting
Safety Culture Involvement Monitoring
-PADS Awareness Behavioural Safety Attitude
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Average Sellafield Exposure 1951 to 2003
Radiation Workers
8,800 Employees 3,700 Contractors
Includes Calder Hall and Contractors