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Radiation Safety TrainingRadiation Safety Training
Module 2 – Safety and RadiationModule 2 – Safety and Radiation
OUTLINEOUTLINE
• SAFE HANDLING TECHNIQUES – PROPER PPE SAFE HANDLING TECHNIQUES – PROPER PPE (PERSONAL PROTECTIVE EQUIPMENT)(PERSONAL PROTECTIVE EQUIPMENT)
• STORAGE AND SECURITYSTORAGE AND SECURITY
• SURVEY INSTRUMENTATIONSURVEY INSTRUMENTATION
• RADIOLOGICAL SURVEYSRADIOLOGICAL SURVEYS
SAFE HANDLING TECHNIQUES – SAFE HANDLING TECHNIQUES – PROPER PPE (PERSONAL PROTECTIVE PROPER PPE (PERSONAL PROTECTIVE
EQUIPMENT) EQUIPMENT)
Safe Handling TechniquesSafe Handling Techniques
Plan experimental procedures to take into account Plan experimental procedures to take into account time, distance, shielding and work on the ALARA time, distance, shielding and work on the ALARA
principle.principle.Fume HoodsFume Hoods
Seal EdgesSeal Edges
Plug SinkPlug Sink
Safe Handling TechniquesSafe Handling Techniques
““Secondary Containment”Secondary Containment”
Must be able to contain all the liquidMust be able to contain all the liquidContainers with lids must be closed when not in Containers with lids must be closed when not in
useuse
Personal Protective EquipmentRequired for using Radioisotopes
• PPE is worn on the body
• Primary purpose is to provide a barrier to radioactive materials or radiation
Eye ProtectionEye Protection
Latex GlovesLatex Gloves
Lab CoatLab Coat
Full Length Dresses orPants ONLY
Complete Complete CoverageCoverageFeet and LegsFeet and Legs
- No Shorts- No Half Shorts- No Open-Toed Shoes- No Mini-Skirts
Engineering ControlsEngineering Controls
VentilationVentilationAccess Control
Safety SwitchesSafety Switches
RAD WASTE CONTAINERSRAD WASTE CONTAINERS
2.5 gal carboy2.5 gal carboy(10 L)(10 L)
(CRS 721925)(CRS 721925)
30 gal. Fiber drum30 gal. Fiber drum
(CRS 768900)(CRS 768900)
LINERS!LINERS!
5 gal plastic5 gal plasticbucketbucket
ALARA FOR RAM STORAGE AREAS
The primary factors associated with RAM storage areas are distance and shielding. No one should spend time around RAM storage areas.
Where you place your RAM and RAD waste is essential in keeping doses ALARA
If an ideal place is not suitable, then shielding should be implemented.
Secondary containment should always be used.
STORAGRE DEPENDS ON TWO STORAGRE DEPENDS ON TWO FACTORSFACTORS
TYPE OF RADIATIONTYPE OF RADIATION STRONG BETA?STRONG BETA?
PHOTON EMITTER?PHOTON EMITTER?
PHYSICAL MAKE-UPPHYSICAL MAKE-UPCHEMICAL?CHEMICAL?
BIOLOGICAL?BIOLOGICAL?MEDICAL?MEDICAL?
SHELF-LIFE?SHELF-LIFE?EXPIRATION DATEEXPIRATION DATE??
RADIOACTIVE STORAGE CONSIDERSTIONSRADIOACTIVE STORAGE CONSIDERSTIONS
WEAK BETAS –( WEAK BETAS –( 33H, H, 1414C, C, 3333P, P, 3535 S) S) STORAGE IN ORIGINAL STORAGE IN ORIGINAL PIG, & SECONDARY PIG, & SECONDARY
CONTAINMENTCONTAINMENT
STRONG BETAS – (STRONG BETAS – (3232P)P) STORAGE IN ORIGINAL STORAGE IN ORIGINAL PIG, INSIDE LUCITE ORPIG, INSIDE LUCITE ORPLASTIC CONTAINER, PLASTIC CONTAINER, SOMETIMES LEAD SOMETIMES LEAD SHIELDING OUTSIDESHIELDING OUTSIDE
ALL GAMMASALL GAMMAS STORAGE IN STORAGE IN ORIGINAL ORIGINAL LEAD PIG, LEAD PIG, SECONDARYSECONDARY CONTAINMENT, CONTAINMENT, EXTRAEXTRA LEAD SHIELDINGLEAD SHIELDING
Know where your RAM is at all times !
Utilize proper and accurate inventory
controls.
Keep this form,“Summary of Isotope Inventory” up to date
at all times
State Requirements for Storage and Control of Licensed or Registered Sources of Radiation
•Must be secured to prevent unauthorized removal or access in unrestricted areas. Under Lock and Key is ideal. If not, area access doors locked, or constant surveillance
•Shall control and maintain constant surveillance if in an unrestricted area.
Radioactive Materials Security
• .03(10) lists SECURITY requirements
• Recent incidents in this country and other states have prompted the NRC to increase security requirements
• All sources of radiation must be All sources of radiation must be secured against theft or use by secured against theft or use by unauthorized individuals -unauthorized individuals - CHECK CHECK SECURITY IN YOUR LAB !!SECURITY IN YOUR LAB !!
• Portable and hand-heldPortable and hand-held• Direct, real time and immediate Direct, real time and immediate
measurements measurements
Measure:Measure:exposure rate in milliRoentgen per hourexposure rate in milliRoentgen per hour
mR/hrmR/hr
Survey InstrumentsSurvey Instruments
Selection of a Survey Selection of a Survey InstrumentInstrument
What type of radiation does the instrument detect?
Some instruments detect more than one type of radiation
It is critical to use an instrument appropriate for the radiation of concern
G-M: can respond to , and : and ; or only depending on the tube/window wall thickness
Thin windowed probes required to pick up weak Betas like C-14
Recommended Survey Recommended Survey InstrumentInstrument
Ludlum model 3 instrument (Part No. 48-1605) with a 202-608 meter dial and extra cable
Recommended Survey Probes
Ludlum model 44-9 (Part No. 47-1539) Alpha, Beta, Gamma pancake probe
General Purpose
Ludlum model 44-3 (Part No. 47-1533) Gamma probe
Low Energy Gamma (10-60 keV, Iodine)
Ludlum model 44-2 (Part No. 47-1532) Gamma probe
High Energy Gamma
What Can The Instrument What Can The Instrument Detect?Detect?
Can the instrument detect tritium?Can the instrument detect tritium?
Can there be contamination that the Can there be contamination that the instrument cannot detect?instrument cannot detect?
There may be contamination that is below There may be contamination that is below the detection limit of the instrument for all the detection limit of the instrument for all nuclides that can be detected using wipe nuclides that can be detected using wipe
tests.tests.
Sensitivity and Energy Sensitivity and Energy ResponseResponse
SensitivitySensitivity – how does the instrument – how does the instrument respond to the level of radiationrespond to the level of radiation
Energy ResponseEnergy Response – response of instrument – response of instrument may depend on the energy of the radiationmay depend on the energy of the radiation
Some instruments over-respond or under-Some instruments over-respond or under-respond to different radiation energiesrespond to different radiation energies
Try to calibrate the instrument relative to Try to calibrate the instrument relative to the nuclide of interest.the nuclide of interest.
Time Constant and Survey Time Constant and Survey SpeedSpeed
Slow setting (s) reduced meter fluctuations, but requires more time to stabilize
Fast setting (f) increases meter fluctuations, but requires less time to stabilize and gives faster readings
Time ConstantTime Constant
Survey SpeedSurvey SpeedBasic speed is 1 detector width per second as close to the
source as possible without touching the source
Does not change the audible signalDoes not change the audible signal
BackgroundBackground
What is the background?What is the background?
High background may indicate:High background may indicate:
• Radiation Field above background• Light Leak in Probe • Humidity Problems• Contaminated Instrument• Incorrect High Voltage • Not Warmed Up • Intermittent Cable Connection (short) • No Background then Malfunction (Maybe OK for Probe)
CalibrationCalibration
Survey Instruments subjected to hard use Survey Instruments subjected to hard use can go out of calibrationcan go out of calibration
Calibration information is attached to the Calibration information is attached to the instrument and is part of your lab recordsinstrument and is part of your lab records
Calibrate to the nuclide of interest if Calibrate to the nuclide of interest if possiblepossible
Some instruments under respond at high exposures Some instruments under respond at high exposures – some GM instruments read 0 and some read off – some GM instruments read 0 and some read off
scale. What does the instruction manual say?scale. What does the instruction manual say?
Calibration FrequencyCalibration Frequency
UGA performs calibrations at least annuallyUGA performs calibrations at least annually
Instrument in calibration if performed Instrument in calibration if performed within one yearwithin one year
For extreme conditions increase frequencyFor extreme conditions increase frequency
Immediately after performance failureImmediately after performance failure
After any maintenance or repair (not After any maintenance or repair (not including battery change)including battery change)
Check SourcesCheck Sources
Specific procedures for check source Specific procedures for check source placementplacement
Long half-life to minimize correction for Long half-life to minimize correction for decaydecay
• No impurities (No impurities (134134Cs, Cs, 137137Cs)Cs) • Chemically stableChemically stable
• Durable with handlingDurable with handling • Cross check with another Cross check with another
instrument instrument
• Contact RSO for check Contact RSO for check sourcessources
Conducting a Performance Conducting a Performance CheckCheck
Check for in service calibration sticker Check for in service calibration sticker
Check battery using battery check positionCheck battery using battery check position
Check for any physical damage to meter or Check for any physical damage to meter or probeprobe
Measure Background and compare to Measure Background and compare to previous bkg historyprevious bkg history
Measure response to check sourceMeasure response to check source
Does speaker work?Does speaker work?
Failure of a Performance Failure of a Performance CheckCheck
DO NOT USE METER !DO NOT USE METER !
Use a back up meter or borrow oneUse a back up meter or borrow one
Remove instrument from use and contact Remove instrument from use and contact the RSO for assistance. Your meter will the RSO for assistance. Your meter will
need maintenance or repair and need maintenance or repair and recalibrationrecalibration
Liquid Scintillation Counting
Set wipe counting protocol to full scale, 1000 channels ( 2000 KeV)
Eliminate counting geometry variables
Do IPC
Know your typical background countrate?
Use biodegradable LSF (Cocktail)
Count BKG before and after sample set.
Dark adapt samples including background
Save all counting printouts
Determination of Minimum Detectable Activity (MDA)
_________________ MDA in dpm = 2.71 + 4.66 √ bkg cpm x count time (eff) (count time)
Is your counting time sufficient for the 200 dpm limit?
MDA is the activity threshold for the counting instrument for a given background…
to decrease this value, increase your counting timeot increase your sample size.
Results less than this value are reported as <MDA
Radiation Surveys
• .03(7) requires radiation surveys and monitoring
• Chapter 6 of the 2003 UGA Radiation Safety Manual covers Radiation Surveys
Radiation Monitoring and Radiation Monitoring and SurveysSurveys
• Measurements of Measurements of radiationradiation AND AND contaminationcontamination to evaluate the radiation to evaluate the radiation hazard
• Contamination is any radioactive material that is in any location where it is not desired.
• Surveys are conducted forSurveys are conducted for restricted restricted and and non-non-restrictedrestricted working areas and areas surrounding working areas and areas surrounding a facility.a facility.
• Hand and Foot or Whole Body surveys are Hand and Foot or Whole Body surveys are recommended when leaving the radiation use recommended when leaving the radiation use laboratory.laboratory.
State Rules for Surveying State Rules for Surveying and Monitoringand Monitoring
Must evaluate:Must evaluate:
•Radiation levelsRadiation levels
•Concentrations or Quantities of Concentrations or Quantities of Radioactive MaterialRadioactive Material
•Potential Radiological HazardsPotential Radiological Hazards
CONTAMINATION SURVEYS
The primary purpose of contamination surveys are to identify the quantity (or
verify the absence) of radioactive contamination on surfaces. The
objective is to prevent the inhalation, ingestion, or absorption of radioactive
contamination by personnel and to ensure that contamination is not
spread to the surrounding environment.
Direct Scan Survey – use of the direct scan technique to measure the activity emitted from a surface. The radiation detected is the total result of any fixed and transferable contamination on the surface, and of any radiation that may be penetrating through the surface or emanating from another source.
TYPES OF CONTAMINATION SURVEYS
TYPES OF CONTAMINATION SURVEYS
Transferable Contamination Survey – An assessment of the amount of readily removable contamination present on a surface. A collection medium is used to wipe a surface while applying moderate pressure. The amount of activity detected on the collection medium is then determined using radiological instrumentation.
TYPES OF CONTAMINATION SURVEYS
100 cm2 Wipe Tests
wipe survey – the use of a collection medium (paper disc or equivalent) to cover approximately 100 square centimeters of surface area in the assessment of transferable contamination.
Wipe TestsWipe Tests
Standard industry practice 100 cmStandard industry practice 100 cm22
12” to 14”12” to 14”100 cm100 cm22
4” x 4”4” x 4”
TYPES OF CONTAMINATION SURVEYS
Large Area Wipe Survey – the use of a collection medium ( paper towel, disposable wipe, or equivalent) to perform a transferable contamination survey of a surface area significantly larger than 100 square centimeters.
Glove Protocols
Survey your gloves at times while wearing them to reduce the spread of contamination
Therefore; CPM from printout x CF = DPM
CPM X 3 = DPMFor wipe tests with whatever Isotope
CPM to DPM Conversion Using the Standardized LSC Wipe Counting Efficiency
LSC standard wipe counting efficiency = 0.33
Correction Factor = 3
Net cpm to equal 200 dpm = 67 cpm
Net cpm to equal 1000 dpm = 333 cpm
Transferable Contamination ALARA Action Levels
Unrestricted Area = 200 dpm/100cm2 (<66 cpm/wipe)
Restricted Area = 1000 dpm/100cm2 (<333 cpm/wipe)
Free Release Transferable Contamination ALARA Action Levels
200 dpm/100cm2 (<66 cpm/wipe)
Radiation SurveysRadiation Surveys
RADIATION SURVEYSThe primary purpose of radiation surveys are to identify the magnitude (or verify the absence) of
dose rates so that personnel exposure to radiation is maintained As Low As Reasonably Achievable
(ALARA).
Types of Radiation SurveysOn Contact
1 foot (30 cm)1 meter
The performance of radiation dose rate surveys is not required in authorized use locations where the radioactive materials are limited exclusively to milliCi quantities of isotopes that emit primarily beta radiation with energies below 250 keV (H-3, C-14, S-35, and P-33). The exclusive use of I-125 immunoassay kits with <25 microCi per kit is also exempted.
You must indicate what isotopes you use in the comments section of your monthly RSF
Use of P-32, I-125 and all gamma producing isotopes require monthly documented radiation surveys on the RSF
Radiation Dose Rate ALARA Action Levels
Unrestricted Area normally occupied for 40 hours per week
<0.05 mrem/hr @ 30 cm (whole body dose rate)
Restricted Area normally occupied for 40 hours per week or unrestricted area with limited occupancy (< 10 hours per week)
<2 mrem/hr @ 30 cm (whole body dose rate)
Any doserate > 5 mR/hr, notify RSO immediately
Questions ???Questions ???
Please Feel Free to Contact: Please Feel Free to Contact:
The Radiation Safety OfficeThe Radiation Safety OfficeEnvironmental Safety DivisionEnvironmental Safety DivisionUniversity of GeorgiaUniversity of Georgia240A Riverbend Road240A Riverbend RoadAthens, Georgia 30602-8002Athens, Georgia 30602-8002
If you have any questions while reading the If you have any questions while reading the Radiation Safety ProceduresRadiation Safety Procedures
542-5801542-5801www.esd.uga.edu
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