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Radiation Safety Program Responsibilities Regulations Authorization (Project) Requirements
US Nuclear Regulatory Commission (NRC) Purdue University Radiation Safety Program Radiation Safety Committee Personnel Principal Investigator (PI) Authorized Users Other Personnel
US NRC (Nuclear Regulatory Commission) The Commission formulates policies, develops regulations governing nuclear reactor and nuclear material safety, issues orders to licensees, and adjudicates legal matters.
Radiation Safety Program: Authorized by Purdue University Executive Memorandum No. B-14 No. B-14 Radiation Safety Committee (RSC) Radiation Safety Officer (RSO) in the Dept. of Radiological and Environmental Management (REM)REM Radiation Safety Staff Radiation Safety Manual
REM serves as a consultant to the University Community in the following areas: Construction Health and Safety, Environmental Health, Fire and Safety Equipment Service, Hazardous Material Management, Industrial Hygiene, Laser Safety, Radiation Safety, and Safety and Ergonomics REM assists in monitoring regulatory compliance with various federal, state, and university regulations involving environmental, health and safety issues. Services include training, consultation, emergency response, and waste removal.
Responsible for complying with regulations set forth by the US NRC, as well as the Indiana State Department of Health, for the safe use of radioactive materials and radiation producing devices. This is accomplished by providing several types of training, radioactive waste pickups, calibration services, personnel dosimetry to monitor radiation exposure, and consulting support for any safety issues identified by Purdue University employees and students.
The mission of the Radiation Safety Committee is to ensure the safety of the University and community in the utilization of all radioactive materials and radiation producing devices at the University or by University faculty, staff, or students.
US NRC Rules and Regulations 10 CFR Part 19 - Notices, Instructions and Reports to Workers: Inspection and Investigations US NRC Rules and Regulations 10 CFR Part 19 - Notices, Instructions and Reports to Workers: Inspection and Investigations US NRC Rules and Regulations 10 CFR Part 20 – Standards for Protection Against Radiation US NRC Rules and Regulations 10 CFR Part 20 – Standards for Protection Against Radiation US NRC Regulatory Guide 8.13 – Instruction Concerning Prenatal Radiation Exposure US NRC Regulatory Guide 8.13 – Instruction Concerning Prenatal Radiation Exposure Many others
Workers Rights: 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 upon written request to the RSO, to request NRC inspection, to be instructed in and required to observe applicable provisions of NRC regulations and licenses, and to be instructed in the appropriate response to warnings.
Occupational dose limits Surveys and monitoring Precautionary procedures Waste disposal Records of surveys Enforcement Storage and control of licensed material
Freedom of Employees in the Nuclear Industry To Raise Safety Concerns Without Fear of Retaliation 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 first addressed within the existing University hierarchy.
Approval Process begins after required forms are submitted to REM. Complete Required Training Follow Laboratory Safety Practices (see Module #4) Recordkeeping Decommissioning
Forms must be completed and approved by RSO, RSC Form A-1: Project Summary & Evaluation for Use of Radioactive Materials and Radiation Producing Devices (New/Amend Project Form) Form A-1 Form A1-S: Radiation Facility Approval Request (New Lab Application) Form A1-S Form A-4: Application to Use Radioactive Materials and/or Radiation Producing Devices (New User Application) Form A-4 Form SM-1: Survey Meter Registration Form SM-1 Training must be completed by all users
Available Training: (General) Radiation Safety Training for Use of Radioactive Materials Sealed Source Training (includes irradiator and nuclear gauges) Diagnostic x-ray (includes DEXA) Analytical x-ray (diffraction) Laser Safety Declared Pregnant Worker DOT Training (Transport of Hazardous Materials) Radiofrequency/Electromagnetic Safety Training Others, as needed Note: Some retraining may be required. Awareness training is also available as needed.
Use Radioactive Material Logbook Keep the most recent authorization printout in this binder Authorized users and locations listed Authorized nuclides, compounds, and amounts Survey Log Waste and Inventory Logs Radionuclide Receipts KEEP YOUR RECORDS UPDATED!
See Module #4 of this training.
All radiation-labeled equipment must be certified HAZARD FREE prior to service or disposal Liquid scintillation counters, gamma counters, and gas chromatographs could contain radioactive sources Prior to moving out of an area and abandoning equipment - notify REM
May obtain an injunction or court order to prevent a violation Civil penalties Criminal penalties willful violation of, attempted violation, or conspiracy to violate any regulation
Radiation Basics Definitions and Units Background Exposure Types ALARA Half-Lives and Decay
Radioactivity Spontaneous emission of particles and/or electromagnetic radiation from an unstable nucleus. Ionizing Radiation Radiation of sufficient energy to strip electrons from the orbit of an atom causing ionization. Contamination Radioactive material in an unwanted location. Half-Life The time required for any given radioisotope to decrease to one-half its original quantity After 10 half-lives, the radioactivity is reduced to 0.01% of the original activity
Exposure - ionization in air Units: roentgen R, (milliroentgen, mR)(C/kg of air) Survey instrument readings (i.e. Geiger-Mueller, Ion) Absorbed Dose - energy deposited in matter Units: rad (millirad, mrad) (Gy, mGy, J/kg) Dose Equivalent - biologically weighted absorbed dose Units: rem (millirem, mrem, Sv, mSv) Measured by dosimetry Derived or Calculated
Activity- quantity of radioactive material millicurie (mCi) 2.22 billion disintegrations per minute (dpm) 37 million disintegrations per second (dps) Becquerel (Bq) 1 dps so 1 mCi = 37 MBq and 1µCi = 37 kBq
Average Annual Background Radiation Exposure in the US is approximately 620 mrem Personal background exposure may be influenced by location and lifestyle Source: NCRP Report #160
There are 4 main types of radiation, each of which has different shielding requirements Alpha Particle made up of 2 protons and 2 neutrons Atomically large Beta Electron particle Moderately easy to shield – avoid lead or high Z material Gamma/x-rays Energy only – not particulate More difficult to shield Neutrons Neutral particle Difficult to shield
Methods Time Distance Shielding Amount Contamination Control Dosimetry Notification trigger level of 100 mrem per wear period for whole body exposure
The less time spent in a radiation area the lower the accumulated exposure to the worker. Plan all work efficiently. It is best to do an experiment using a non radioactive surrogate and allow someone to watch the your technique, or videotape the work. Reducing time will reduce exposure.
The greater the distance the lower the exposure. Your goal should be to never allow the distance between you and any source to become zero. Therefore: Never touch any source if you can avoid it. Use tweezers, tongs, holders, racks, or other engineered fixtures. Move sources to the back of hoods or in other ways away from personnel.
Inverse Square Law (Point Source) Intensity of Radiation decreases as the inverse square of the distance. Doubling distance, exposure = ¼ of original; Tripling distance = 1/9 of original exposure I1dI1d = I 2 d
Always use shielding. The greater the shielding the lower the exposure to workers. 1 cm of plastic for most Betas. Lead for gammas, or x-rays. Graded shielding is best, i.e. plastic first then mass like lead. Check effectiveness of shielding with a meter.
The smaller the amount of radioactive material the lower the exposure. Use the smallest volume or the lowest specific activity needed for an experiment. Remove debris from the work area. Clean the area. Decontaminate when contamination is found. Survey the area on a regular bases. Do your wipe tests on a regular basis.
Individuals working with significant amounts of radioactive material are provided dosimetry to measure their radiation exposure When exposures exceed specified low trigger limits of 100 millirem during the period (monthly or bimonthly) the user is notified A form must be completed and returned to acknowledge that the user is aware of the exposure and will take steps to reduce if possible
Biological Effects from Radiological Exposure Routes of Exposure Biological Effects Risk Analysis
An individual can be exposed to radiation: Internally Intake by mouth, nose, eyes, or any open cut Externally Energy is passed through the body and/or absorbed by tissues Contamination Residual radioactivity on the skin irradiates skin and other tissues
External (high energy beta, gamma, neutron) Internal (alpha, low energy beta) Inhalation Ingestion Injection (wound) Absorbtion An individual can be exposed to radiation through these routes:
Acute (one-time) high level dose Can cause radiation damage and symptoms quickly Chronic (long-term) low level dose Body has time to repair/replace damaged cells Effects, if any, appear after years Risk of cancer with 1 rem of radiation increases from the normal rate of 20% to 20.03% Acute effects are highly unlikely using millicurie amounts of radioactivity in a research setting
SymptomDoseTo Target Nausea, Diarrhea100 remWhole Body Cataracts200 remEyes Erythema300 remSkin Sterility in men500 remGonads Death (LD 50/60 ) - no treatment300 remWhole Body Death (LD 50/60 ) - with treatment600 remWhole Body Gastrointestinal Syndrome 600 remWhole Body Cerebrovascular Syndrome 3000 remWhole Body *Source: Merck Manual Online Medical Library
Stochastic (by chance): the effects have no threshold and the severity of the effect does not vary with the dose Cancer (including leukemia) Deterministic: the effects have a threshold and the severity of the effect does vary with the dose Cataracts
High doses - there is a correlation between dose and effect Low doses (<10 rem) - it is unclear what the risk is at this level. BEIR VII Report assumes linear no-threshold dose response, so any dose could have a negative effect – doses are maintained As Low As Reasonably Achievable (ALARA) Hormesis – some scientists believe that low doses of radiation may be beneficial
Laboratory Safety Posting and Labeling Facility Classification Eating, Drinking, Smoking, Application of Cosmetics Personal Protective Equipment Equipment Maintenance
In room/area Door: Lab Classification Near radioactive waste: Waste PosterWaste Poster On equipment used for radioactive materials Radioactive materials label Do not place Radioactive Materials label on something that is not used for radioactive materials or is not radioactively contaminated
While the consumption of food and beverages is generally discouraged in chemical labs, restrictions are different for each laboratory class.
The use of food containers for handling or storing radioactive materials is not permitted. Any other containers used must be clearly marked as containing radioactive material. See Section 9.2 of the Purdue University Radiation Safety Manual.Purdue University Radiation Safety Manual
A minimum of gloves, lab coat and shoes that cover the feet are required for work with unsealed sources of radioactive material For operations with splash potential - safety glasses or goggles are required Remember that gloves should not be worn outside the lab – this has the potential to spread contamination.
For contamination control, but not considered shielding Remove when finished with handling material or when contaminated; whichever comes first Consider double-gloves during procedures that are likely to contaminate Monitor your gloves frequently and change when they become contaminated
All equipment used for radioactive material use MUST have a radioactive materials label affixed. If equipment requires maintenance, remove materials from area and clean surfaces. Attach Hazard Clearance and Declaration Form (aka: Clean Sheet) to equipment.Hazard Clearance and Declaration Form
Surveys must comply with the regulations and determine the extent of the radiation levels, concentrations or quantities of radioactive material, and potential radiological hazards
Survey Meter or Rate Meter with an associated: Geiger-Mueller (G-M) Pancake Probe Geiger-Mueller (G-M) End-Window Probe Sodium Iodide (NaI) Probe Alpha probe Liquid Scintillation Counter Ion Chamber Best for P-32 For counting wipes for removable contamination
Measures both fixed and removable beta (with exception of low-energy beta emitters such as H-3), gamma, and alpha contamination. Can accommodate different probes End-window, pancake NaI scintillator Alpha Meter efficiency can vary widely due to: Energy of radionuclide Geometry
These are dose reading type survey meters. Usually have a door or cap over the window. Most application is found in differentiating beta verses gamma dose. Many Dose Calibrators are ion type chambers. Work on the principle of air ionization.
Ion chamber usage. Readings are usually recorded with the door both open and closed. This gives beta plus gamma and gamma only reading. Used in finding dose in an area or shielding effectiveness. Open (beta & gamma) Closed (gamma only)
Lab surveys should be performed on a regular basis to prevent contamination in the laboratory and to keep exposures to personnel ALARA (As Low As Reasonably Achievable). The frequency of surveys will depend on the amount of radioactive material used and the experimental procedures. Perform surveys during the experiment and at the end of each experiment. Clean up any contamination found. A survey of the use area should be performed and documented: Monthly - if material is used at all Weekly - if greater than 1 mCi is used Daily - if greater than 5 mCi is used If no material was used during the month, document this. Proper technique is important – move the probe slowly over the area to be surveyed at a close distance, within ¼ inch of surface. It is preferable that the authorized user performing the experiment also be the one performing the survey (this person should know the potential areas of contamination). Make a record of the survey- example on next page
Project Director ________________________started on ____________ (date) Bldg____________________ Room # _________________________________ * Areas surveyed at a minimum should include bench top, floor, waste area, equipment, and other areas that could potentially be contaminated equipment. Maintain records for 3 year minimum.
Is it working? Will it detect the type of radiation of interest? Will it detect the level of radiation expected in the area? What is background in the area? Is the instrument in calibration? Do I know the meter scale factor?
Is it Working? Check battery level and meter integrity. Replace the batteries as necessary. REM recommends alkaline type batteries as they do not leak as often. Use known source to check operation. Use the audio if the instrument has a speaker. Use most sensitive scale (i.e. lowest scale x0.1 or x1) if possible. Notify REM for assistance with survey meter problems.
Will it detect the type of radiation of interest? Tritium will not be detected by a common survey meter. You must perform a wipe test, counted with a liquid scintillation counter or other window-less counting system. Carbon-14 will be detected with very low efficiency.
Will it detect the level of radiation expected in the area? Is the meter made for detecting background levels? Note: Some meters sold on the Internet for as little as $25 will not detect typical laboratory contamination at all.
What is background in the area? Background radiation in laboratories can vary greatly. Sources or radioactive waste can contribute to background. It is difficult to find contamination in a high background area.
Is the instrument in calibration? Check the calibration due date on the sticker or tag affixed to the instrument. The instrument must be within the dates given. REM has a calibration service for the University. If the instrument is out of calibration, notify REM for calibration.
Do I know the meter scale factor? Some meters give you a multiplication factor. Other meters show you the topmost reading expected on the scale. Some types give a different scale for X100. Check yourself as scales can be confusing.
Scaler Dependent (what scale are you on?) Example: Using the x10 scale, the meter reads 15,000 CPM for contamination, or Approx mR/hr for radiation exposure
Measures removable contamination that could be spread to other areas Perform with moderate pressure over at least 100 square centimeters Count the filter in an appropriate counter Focus on areas where contamination could be easily spread - FLOORS!
A wipe test is the most sensitive way to detect removable contamination. covers a large surface area high efficiency when counted by liquid scintillation (LSC) only practical measure of 3H contamination Efficiency of removal - approximately 10% For high energy beta emitters, wipes can be checked with GM meter
Protocols can be tailored to counting needs Keep as survey record documentatio n > 200 dpm in any channel indicates contaminatio n
Used to convert observed count rate (cpm) to activity (dpm). Determined by counting a known standard with the instrument. Efficiency (Eff) = cpm/dpm x 100% E.g.: If a GM counter has an efficiency of 5% (.05), what activity is present when it reads 300 cpm? 0.05 = 300/X Therefore, the activity present is 6000 dpm.
IsotopeEnd-Window (% efficiency)Pancake (% efficiency) C-1415 S P I
H-350 percent C-1490 percent S-3590 percent P-3295 percent I percent Your results may vary depending on counter, quenching, etc.
Monitoring is required for those likely to receive, in 1 year from sources external to the body, a dose in excess of 10 percent of the occupational exposure limits.
Passive (most commonly issued at Purdue) Thermoluminescent Dosimeters (TLDs) Film Badges Active Pocket Electronic
Wear correct dosimeter Wear dosimeter in correct location Store in low background area when not in use Do not remove from occupational location Avoid physical damage (e.g. water, heat, impact) Report unusual occurrences to REM that may effect dosimetry integrity/readings
Proper placement: Whole Body: Outside of clothing Front side of body Between neck and waist Ring: Under gloves (minimizes potential for contamination) Chip side (name plate) facing palm Worn on hand most likely to receive greatest dose. Fetal: Outside of clothing Abdominal area
Wear this on palm side.
Total Effective Dose Equivalent (TEDE) Whole Body - Annual 5 rem Dose Equivalent to Any Organ or Tissue (TODE) - Annual 50 rem Dose Equivalent to the Skin or Extremities (SDE) - Annual 50 rem Dose Equivalent to the Lens of Eye (LDE) - Annual 15 rem Dose Equivalent allowed to Embryo/Fetus (Declared Pregnant Worker)– 9 month gestation period 0.5 rem This is a voluntary declaration that, if the declaration is made, must be done so in writing to the RSO. Note 1: Annual Occupational Dose Limits for Minors (i.e. personnel under 18 yrs. of age) is 10% of the adult limit. Note 2: Non-occupational (i.e. general public) TEDE is limited to an annual limit of 0.1 rem, and an hourly exposure limit of 2 mR.
Low energy beta emitters (e.g. H-3, C-14, P-33, S-35, Ca-45) No dosimeter issued Higher energy beta emitters (e.g. P-32, Sr-90) Ring dosimeter issued for 1 mCi Whole body dosimeter issued for 5mCi Low energy gamma emitters (e.g Cr-51, Co-57, I-125) Ring dosimeter issued for 1 mCi Whole body dosimeter issued for 5mCi Higher energy gamma emitters (e.g. Na-22, Co-60, Cs-137, I-131) Ring dosimeter issued for 0.1 mCi Whole body dosimeter issued for > 1.0 mCi Neutron emitters (e.g. Tritium generators, Cf-252) Extremity dosimeter issued for 10 mCi Whole body dosimeter issued for any use
Return dosimetry promptly! If dosimetry is not returned, it cannot be processed. Dosimeters returned late may be considered degraded and unreadable. Also, there is a cost (late fee) associated with unreturned dosimetry. Notify REM if you will not work with materials requiring dosimetry for extended periods. We can suspend your service and reactivate it when it is needed.
Procurement & Receiving Radioactive Material (RAM) Procurement Receiving RAM
Consult with REM personnel, RAM procurement webpage.RAM procurement webpage All packages containing radioactive material must be shipped to REM at CIVL B203 to go through a required check-in process. When ordering, attach Form R-1 in OnePurdue order.Form R-1 Only approved radioisotopes, chemical forms, and amounts may be ordered.
Remember to place orders before Noon (12 PM) Please allow 3 business days when ordering because: All individuals in the approval process must approve the order Technical problems are not uncommon Special Note: Vendors take holidays, too! On long holiday weekends, shipments will not be sent out until vendor returns from holiday.
Deliveries will be made after 1 PM on the day that REM receives the shipment from the vendor. Only laboratory personnel who are knowledgeable and are able to immediately secure the material should physically receive the RAM from REM. The receiver will sign for confirmation of receipt, and keep a copy for laboratory records.
Order only what you will immediately use Consider an aliquot into separate vials to avoid reopening and subjecting compound to warming and cooling cycles Store material according to manufacturers recommendations
Waste Management & Disposal General Information Procedures Radioactive Waste Management Summary
ALL containers provided by REM Follow YELLOW waste flow chartYELLOW waste flow chart Segregate P-32/P-33 (short half-life) from long-lived isotopes Waste is picked up on Tuesday ONLY Waste Pickup Request Form
The following information is needed on all waste labels if ANY waste is in the container. Liquid Waste Authorization # Radionuclide Amount (in mCi) Date waste was added Solvents in the container pH (must be 6 and 9) Solid Waste Authorization # Radionuclide Amount (in mCi) Date waste was added pH (must be 6 and 9)
Separate waste between long and short half-life. (Short is defined as less than 30 days) Declare all chemicals in a percentage format Record pH of solution List all radionuclides and amounts in mCi Date when container is sealed or full Do NOT abbreviate or use acronyms for chemicals or solutions (e.g. use phosphate buffered saline, water NOT PBS or H 2 0)
Record the amount and the date every time something is added to the container. Use a separate sheet if necessary. Complete a Waste Pickup Request when container is nearly full or wont be used for extended periodsWaste Pickup Request
Waste Scintillation Vials Place flats containing waste vials upright in original box; tape box shut Label box with radioactive waste label For vials shipped in bulk Cap tightly Use rigid container (radwaste bucket) To contain leakage, double bag with absorbent material* between bags *Absorbent material will be supplied by REM
Waste Tips Radioactivity predominantly in liquid form Total activity in liquid and solid should be no more than originally ordered Keep a running total of waste added to each container Use absorbent paper around carboy opening to limit container contamination Keep vendor containers separate from other waste
Segregate radioactive waste according to waste segregation poster. Enter radionuclide and activity disposed into each container in waste log book. Label containers to be picked up with: Radionuclide(s), Activity, Authorization number, Date, pH (if liquid), Solvents and percentages (if liquid) Seal containers (use zip tie, tape or staple shut if bag, cap if carboy, screw on lid of bucket, tape scintillation vials into original box, seal or close sharps container) Submit online waste pickup form to REM.waste pickup form It is suggested that a waste log be kept near the waste area to keep a record of the isotope and activity added to each container to aid the person preparing the radioactive waste for pickup in labeling the waste.
Transfer & Transportation RAM Transfer RAM Transportation
All RAM transfers must be approved by REM prior to transfer On-Campus: receiving individual must be authorized to possess type and amount of material Off-Campus: Only REM will ship or receive material Non-vendor sources (i.e. gifts, joint research) Will be treated in same manner as vendor sources
Transportation of radioactive materials will be done through REM, as a general rule. PIs on campus may only transport radioactive materials under the specific approval by the RSO. DOT (Department of Transportation) regulatory requirements must be met Packaging Labeling Emergency Contacts Other requirements
Typically contamination incidents have been with P-32 at research institutions The incidents occurred because researchers did not perform a proper survey The contamination was spread to areas such as cars, churches, and homes These would likely have been prevented if the lab performed proper surveys Resulted in notices of violation from NRC
An area is considered contaminated if: Survey meter is twice background (be aware that you could be detecting a source), and/or Wipe test results indicate > 200 dpm in any channel If a survey or wipe indicates contamination Decontaminate using disposable towels and soap or decontamination solution If bench paper is contaminated, dispose in radioactive waste Continue the process until the area is no longer contaminated If there is floor or personnel contamination, notify REM immediately
Response is dependent on type of emergency. Personal Injury Spills (Major and Minor) Fire Medical problems take priority over radiological concerns.
Personal Injury Treat injured personnel first. Administer any life- saving procedures without regard for contamination. Do not move a seriously injured person unless he or she is in further danger. Contact medical personnel (i.e. call 911). Notify REM ( ).
Major and Minor Spills See Radiation Safety ManualRadiation Safety Manual Notify REM between 8-5 CALL (or if no one can be reached) After hours CALL Purdue Police at 48221
Fire Activate the building fire alarm system (fire pull station). If not available or operational, verbally notify persons in the building. Notify the Fire Department at 911. Isolate the area and evacuate the building: Shut down equipment in the immediate area, if possible. Close doors to isolate the area. Use a portable fire extinguisher to control a small fire or assist in evacuation if possible. Provide the fire/police teams with the details of the problem upon their arrival. Notify Radiological and Environmental Management at
Licensed Material: Shall be secured from unauthorized removal, or Shall be controlled and maintained under constant surveillance.
Security of Radioactive Material Lock freezers or storage areas Lock doors when lab is unattended to prevent unauthorized access to radioactive material and other lab equipment Obtain a lockbox from REM if needed NRC Places High Priority on Security The NRC conducts security screens during campus inspections to evaluate security adequacy. Incidents at other campuses have kept the focus on security. Labs have been found unsecured by the NRC in the past – repeat violations may negatively impact our license!
Secure laboratories when unoccupied Secure RAM if laboratory security is not feasible Challenge visitors or unauthorized individuals Account for RAM through inventory records
James F. Schweitzer, Ph.D Radiation Safety Zach Tribbett Health Sharon K. Rudolph Isotope Ordering & Jerry J. Gibbs Waste Handling & Meter Mike Nicholson Waste Handling & Animal Hospital REM Main Office Civil Engineering Building, Room B173www.purdue.edu/remwww.purdue.edu/rem
To complete the online training, you must take a short test. A score of 75% or better is considered passing. Upon successful completion of the test, you will receive an confirmation. Included in this is the link to sign up for the required classroom session. A list of available dates are present in the online registration.
Bring a completed Form A-4 (make sure that both you AND your Principal Investigator have signed the form) to the classroom session.Form A-4 Thank you! Click here to begin the test. Click here to begin the test. Click here to begin the test. Click here to begin the test.