Transcript Radiation Safety Training 1 hour session

Sealed Source Safety Training for
Ni-63 ECD Sources
Radiological & Environmental Management
Purdue University
Training Goals
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Basic Radiation Safety Principles
Familiarization with Regulations
Purdue’s Policies and Procedures
Why do I need training?
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The gas chromatograph you possess contains an ECD
(electron capture detector)
The detector has a foil which can contain up to 15 mCi of
Ni-63 (which is a radioactive isotope)
The US Nuclear Regulatory Commission require training
for individuals that use or possess radioactive material
When used properly, there is no measurable radiation
exposure
What is radioactivity?
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Radioactivity is an energy
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This energy is produced when an unstable nucleus
spontaneously emits particles and/or electromagnetic radiation
Radioactive material sources
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Sources are characterized as either sealed or unsealed (or
“open”)
To qualify as a “sealed” source, the source must pass a battery
of tests and be certified under NRC regulations
The Ni-63 ECD is a plated foil source that retains its integrity
to prevent release of radioactive material
Pictures of common sealed sources
Ionizing Radiation Types
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Alpha
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Smaller particle (electron), distance traveled ranges from several
inches to a few feet (depending on its energy)
Gamma
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Molecularly large particle (2 protons and 2 neutrons), give up their
energy in a short distance (approximately 1 ½ inches in air)
Beta
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Ni-63 decays by low energy
Beta emission
Non-particulate energy wave, can travel several feet and easily
penetrates material with low atomic mass
Neutron
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Neutral particle, can travel greater distances than gamma radiation
and easily penetrate material with low hydrogen ion concentrations
Risks of Radiation Exposure
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An average person in the United States receives annual
radiation dose of ~620 mrem, which includes exposure
received from cosmic and natural radiation, medical
treatment, and consumer products.
Large doses of radiation have been known to increase
risk of cancer, birth defects, and possibly genetic effects.
Low doses seem to show no statistical differences in
biological risk; however, some people believe there is risk
at all levels above background exposure.
At radiation levels around 1 rem, it has been estimated
that the increased incidence of cancer is 0.03% - the
normal incidence of cancer for the average person is 25%.
Risk of developing genetic effects is half the risk of cancer.
4 Factors to Reduce Exposure
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It is the goal of our facility to reduce radiation exposures to be
As Low As Reasonably Achievable (ALARA). We achieve this
goal using:
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Contamination Control
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Time
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do dry run, practice procedure to minimize time
Distance
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gloves, lab coats, fume hoods, absorbent paper
a little distance between you and a source can significantly decrease your
exposure from it (follows the “Inverse-Square Law”)
Shielding
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Use proper shielding between you and a source to decrease personal
exposure
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betas - wood, Plexiglas
gammas - lead, leaded glass
Due to the low energy of the beta particle, contamination
control is the only factor needed.
Ionizing Radiation Shielding
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Different shields are needed to minimize external exposure
Rules Governing Use of Radionuclides
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Must be licensed by the Nuclear Regulatory Commission
or state agency
Radiation Safety Officer (RSO) develops and maintains a
Radiation Safety Manual, which must be followed by
individuals working under the NRC license, and it is
enforceable by law
Applicable Regulations
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10CFR19
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Rights and responsibilities
10CFR20
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Standards for protection against radiation
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Declared pregnant worker
Security of radioactive materials
10CFR Part 19
Required instruction to workers
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Rights
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to be informed of storage, transfer, and use of radioactive
materials
to further instruction on health protection problems
associated with radiation exposure and procedures to
minimize exposure
to receive radiation exposure history
to request an NRC inspection
to be instructed in and required to observe applicable
provisions of NRC regulations and licenses
to be instructed in the appropriate response to warnings
NRC Policy Statement
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Retaliation against employees or students engaged in
protected activities, whether they have raised safety
concerns within the University or to the NRC, will not be
tolerated
Problems should be addressed within the existing
University hierarchy – contact the radiation safety office if
you have any concerns regarding issues involving
radioactive materials.
10CFR20 Contents
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Occupational dose limits
Surveys and monitoring
Precautionary procedures
Waste disposal
Records of surveys
Enforcement
Storage and control of licensed material
10CFR20
Occupational Dose Limits
Target
Dose Limit
Whole Body
5 rem/yr
Organ or Tissue
50 rem/yr
Skin or Extremities
50 rem/yr
Lens of Eye
15 rem/yr
Minor (i.e. non-adult)
10% of adult limits
Declared Pregnant Worker
0.5 rem per 9-month gestation period
All dose limits include exposure from both internal and external sources.
Radiation Units
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Exposure= ability of photons to ionize air
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Absorbed Dose= energy deposited in matter
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Roentgen (milliroentgen, mR)
Geiger-Mueller readings
Rad (millirad, mrad)
Dose Equivalent= biological weighted absorbed dose
(tissue)
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rem (millirem, mrem)
Film badge
Acute Effects of Radiation Exposure
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Non-stochastic (cause and effect)
Threshold
Lethal Dose (LD50) is about 600 rad
Examples
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erythema (skin reddening)
blood changes (white blood cells)
Gastrointestinal Syndrome
These effects are not possible under any circumstances
with ECD sealed sources
Delayed Effects of Radiation Exposure
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Stochastic (by chance, statistical basis)
No threshold
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Cancer
Leukemia
Cataracts
Life Shortening
Data extrapolated from high dose data
If the integrity of the ECD source is maintained there is
no measurable radiation exposure.
Risk Analysis
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High doses - there is a correlation between dose and
effect
Low doses (<10 rem) - it is unclear what the risk is at
this level
Hormesis - low doses of radiation may be beneficial
Surveys
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No surveys by the user are required for routine ECD use
REM will be conducting “leak tests” on sealed sources to
evaluate whether the source containment is intact
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this will be done at 6 month intervals.
If there is damage to the ECD or gas chromatograph
please notify REM and a survey will be performed.
Security
NRC Area of Emphasis
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Secure laboratories when unoccupied
Challenge visitors or unauthorized individuals
REM accounts for RAM through inventory records
The goal is to prevent unauthorized access
or use of radioactive materials.
Checklist for compliance and safety
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Operate the GC only within the parameters established
by the manufacturer
Never open or attempt to service the ECD on your owncleaning must be done by an authorized provider
Notify REM before moving or disposal of the GC
Ensure that the GC is labeled as containing radioactive
material
Notify REM immediately is the unit or source is lost or
missing
Notify REM for shipment of the source for service,
Department of Transportation rules must be followed for
shipment
Emergency Procedures
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Call 911
Assist personnel
Monitor personnel
Control area - inform other workers
Notify radiation safety office
Severe Personal Injury
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Medical needs come first! Postpone monitoring, call 911,
notify of radioactive material use
Wait for medical personnel - calmly advise radioactive
materials may be involved if that is the case
Notify REM to assess if there may be contamination from
the source
Review
Always use ALARA
 No eating, drinking, or smoking in labs
 Always secure materials, lock doors
 Never allow unauthorized users access to
radioactive materials
 Call REM for any related questions (4946371)
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 All
Emergencies – call 911
REM’s Radiation Safety Group
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James F. Schweitzer, Ph.D.
Radiation Safety Officer
49-42350
[email protected]
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Mary J. R. Handy, CLSO
Laser Safety Officer, Assistant RSO
49-42721
[email protected]
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Chris Echterling
Health Physicist
49-41478
[email protected]
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Sharon K. Rudolph
Isotope Ordering & Distribution
49-47969
[email protected]
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Jerry J. Gibbs
Waste Handling & Meter Calibration
49-40207
[email protected]
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Mike Nicholson
Waste Handling & Animal Hospital Support
49-40205
[email protected]
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REM Main Office
Civil Engineering Building, Room B173
49-46371
www.purdue.edu/rem
Test
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Complete the test indicated below.
You must have a minimum score of 75% to pass
Complete a Form A-4 (make sure that both you AND
your Principal Investigator have signed the form).
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Send your Form A-4 through campus mail to Sharon
Rudolph/REM/CIVL.