1. University of Notre Dame
Department of Risk Management and Safety
2014 Radiation Safety
Refresher Training

2. INTRODUCTION
Lessons 1-5 will provide a review of some general knowledge of radiation with which all radioactive material and radiation producing machines should be familiar.
Lessons 6-14 address specific safety practices and procedures applicable to laboratories at Notre Dame

3. Lesson 1 Forms of Radiation

4. Forms of Ionizing Radiation
Ionizing radiation includes emissions with energies greater than 20 electron volts that cause ionizations when interacting with matter.
Sources of ionizing radiation at Notre Dame include:
Photon Radiation
Gamma
X-Ray
Particulate Radiation
Alpha
Beta

5. Particulate Radiation
ALPHA RADIATION
Consists of two protons and two neutrons (helium nucleus)
Massive size, moving at 80% the speed of light
Internal Hazard
BETA RADIATION
Consists of an electron
Very small size moving at up to 99% the speed of light
Hazard depends on decay energy of isotope

6. Examples of Beta Emitters
H-3: Energy max = 19 Kev: Internal Hazard
C-14: Energy max = 160 Kev: Internal Hazard
S-35: Energy max = 170 Kev: Internal Hazard
P-32: Energy max = 1700 Kev: Internal and external hazard
The lower energy beta emitters are less penetrating and present less of a hazard. The concerns with these isotopes is primarily associated with internal exposure due to ingestion, inhalation, or skin absorption
Higher energy beta emitters are more penetrating and present both internal and external hazards

7. Photon Radiation GAMMA RADIATION X-RAYS
A wave radiation consisting of a photon
Travels at the speed of light
Created in the nucleus of the atom
X-RAYS
A wave radiation consisting of a photon
Travels at the speed of light
Created in the electron shell of the atom

8. Examples of Gamma Emitters
I-125: Energy max = 35 Kev: Internal/External Hazard
Cs-137: Energy max= 662 Kev: Internal/External Hazard
Gamma Emitters have no mass and are very penetrating
All gamma emitting isotopes and are considered both internal and external hazards

9. Bremsstrahlung Radiation
Literally: breaking radiation
Electromagnetic radiation produced when an electrically charged particle is slowed down by the electric field of an atomic nucleus
Example: The beta particle emitted by a P-32 atom will interact with lead to give off an x-ray
Bremsstrahlung production must be considered when planning the shielding of high energy beta emitters e-
X-ray

10. Lesson 2 Units of Radioactivity

11. Units of Radioactivity
The Becquerel (Bq) - International Unit
1 Bq = 1 disintegration per second
1 MBq = 1,000,000 disintegrations per second
1 GBq = 1,000,000,000 disintegrations per second
The Curie (Ci) – Commonly used in the United States
1 Ci = 3.7E10 disintegrations per second
1 Ci = 2.2E12 disintegrations per minute
1 Ci = 1000 millicurie (mCi) = 1,000,000 microcurie (uCi)
1 Bq = 2.7E-8 mCi

12. Units of Radioactivity
The RAD is the unit commonly used in the United States for Absorbed Dose (D)
It is determined by the Energy that is actually deposited in matter
1 Rad = 100 ergs of deposited energy per gram of absorber
Gray
International Unit for Absorbed Dose
1 Gray = 100 Rads

13. Units of Radioactivity
REM
The REM is the unit commonly used in the United States for the Dose Equivalent
Determined by Multiplying the absorbed dose (D) times a quality factor (Q)
Q equals 1 for beta, gamma and x-rays,
5-20 for neutrons, and 20 for alpha
Sievert
International Unit for absorbed dose
1 Sievert = 100 REM

14. Units of Radioactivity
Most labs at Notre Dame will use only beta, gamma and/or x-ray emitters
The Quality factor for these forms of radiation is equal to 1
Therefore the Rad is equal to the Rem
If your lab is one of the few using alpha, remember that the QF is 20. Therefore, one Rad of alpha is equal to 20 Rem.
Exposure reports are documented in mREM
1 REM = 1,000 mREM

15. Lesson 3 Half Life

16. Half Life
The half life of a materials is the time required for 1/2 of the radioactive atoms to decay
The half life is a distinct value for each radioisotope

17. Half Life of Selected Radioisotopes
Flourine-18: minutes
Phosphorus-32: days
Tritium: years
Carbon-14: 5,730 years
Uranium: 4,500,000,000 years

18. Example of Half Life You receive a shipment of 250 µCi of P-32
The half life of P-32 is 14.3 days
If you do not use the P-32 until 14.3 days after receiving the material, you will only have 125 µCi left
If you wait 28.6 days, you will only have 62.5 µCi left
It is important to consider the half life of the radioisotope when planning a study that includes the use of radioactive materials

19. Lesson 4 Background Radiation

20. Background Radiation
Natural and man-made sources of radiation everybody is exposed to in their daily lives
Typically 20 to 30 mRem per month

21. How Might I Be Exposed?

22. Average Annual Exposure to the General Public
Cosmic
Terrestrial
Radon
Medical
Total
30 mRem
40 mRem
230 mRem
90 mRem
390 mRem

23. Lesson 5 Biological Effects & Risk

24. Biological Effects
Data is largely based on high exposures to individuals within the first half of the 20th century
Biological effects occur when exposure to radiation exceeds 50 rads over a short period of time
All occupational exposures are limited by city, state, or federal regulations

25. Radiation Damage Mechanical: Direct hit to the DNA by the radiation
- Damages cells by breaking the DNA bonds
Chemical: Generates peroxides which can attack the DNA
Damage can be repaired for small amounts of exposure

26. Radiosensitivity Muscle Radioresistant Stomach Radiosensitive
Bone Marrow Radiosensitive
Human Gonads Very Radiosensitive

27. Radiation Effects
Acute Effects: Nausea, Vomiting, Reddening of Skin, Hair Loss, Blood Changes
Latent Effects: Cataracts, Genetic effects, Cancer

28. Dose Required for Acute Effects
If an individual receives a dose in excess of 50 Rem (50,000 mRem) in a short period of time, he/she will experience acute effects

29. Risk of Cancer The level of exposure is related to the risk of illness
While the risk for high levels of exposure is apparent, the risk for low levels is unclear
It is estimated that 1 rem TEDE of exposure increase likelihood of cancer by 1 in 1000
The likelihood of cancer in ones life time is
1 in 3 from all other factors

30. Factors Affecting Risk
The amount of time over which the dose was received
The type of radiation
The general health of the individual
The age of the individual
The area of the body exposed

31. Lesson 6 Occupational Exposure

32. What are the Occupational Exposure Limits ?
Whole Body
Extremities
Skin of Whole Body
Lens of Eye
Thyroid
5,000 mRem/year
50,000 mRem/year
15,000 mRem/year

33. Other Occupational Limits
ALARA - As Low As Reasonably Achievable. This is our policy AND the NRC’s: Don’t expose yourself to radiation any more than absolutely necessary.

34. Exposure to the General Public
Annual limit of 100 mRem to individuals
This includes anybody in the laboratory who does not work for Notre Dame
Examples: salesmen, vendors, family members, etc.

35. Prenatal Radiation Exposure
In the embryo stage, cells are dividing very rapidly and are undifferentiated in their structure and are more sensitive to radiation exposure
Especially sensitive during the first 2 to 3 months after conception
This sensitivity increases the risk of cancer and retardation

36. Declaring Pregnancy
Additional dose restrictions are available for the pregnant worker
Receive a monthly dosimeter
Limited to 500 mRem during the term of the pregnancy
Also, limited to 50 mRem per month
DECLARATION IS STRICTLY OPTIONAL

37. Exposure to Minors Individuals under the age of 18
Must not receive an exposure greater than 10% of occupational exposure for adults
Wholebody Exposure Limit: 500 mRem
Minors will wear dosimeters in laboratories licensed for radioactive material use
Minors should not work with radioactive material

38. Lesson 7 Minimizing Exposure

39. How Do I Protect Myself?
Reducing the dose from any source radiation exposure involves the use of three protective measures:
TIME
DISTANCE
SHIELDING

40. Time
The amount of exposure an individual accumulates is directly proportional to the time of exposure
Keep handling time to a minimum

41. Distance
The relationship between distance and exposure follows the inverse square law. The intensity of the radiation exposure decreases in proportion to the inverse of the distance squared
Dose2 = Dose1 x (d1/d2)2

42. Shielding
To shield against beta emissions, use plexiglass to decrease the production of bremsstrahlung radiation.
If necessary, supplement with lead after the plexiglass
To shield against gamma and x-rays, use lead, leaded glass or leaded plastic

43. Internal Exposure
Only a few commonly used radionuclides at Notre Dame present an external exposure potential
All radionuclides present a potential for internal exposure if taken into the body. Entry into the body can occur by inhalation, ingestion, or absorption through the skin

44. Minimizing Internal Exposure
Wear personal protective equipment
If required, use a fume hood
No eating, drinking or applying cosmetics
Clean up spills promptly
Routinely monitor work area
Secure radioactive material

45. Minimum Protective Equipment
Laboratory coat
Gloves
Safety Glasses
Dosimeters (for certain nuclides and/or machines)

46. Lesson 8 Regulatory Requirements

47. Notre Dame’s License
Broadscope license issued by the Nuclear Regulatory Commission
Permits the use of radioactive material in research and development, as well as education.
Must be renewed every 10 years

48. Radiation Safety Requirements
Radiation Safety Officer
Radiation Safety Committee
Approved Responsible Investigators
Radioisotope Users

49. Records to be Kept on File
In the Laboratory
- Receipt of material
- Utilization of material (logs)
- Waste disposal
- Monthly Wipe tests
-Training verification
By Radiation Safety
-Principal Investigator
-Isotope limits
-Receipt of material
-Waste transferred
-Lab inspections
-Exposure reports
The NRC Inspectors will look specifically for these completed documents in the lab Radiation Safety notebooks which should be stored in every radiation lab.

50. Records (Continued)
If radioactivity is not used or stored during a month, a signed statement may be substituted for a wipe test
Example of Signed Statement:
“There has been no radioactive material use or storage in lab ____ during the month of ____”.

51. Radiation Safety Inspections
Inspections are conducted at least every other month
Review isotope use records and wipe test records
Confirm appropriate postings and labels
Personal protective equipment and dosimetry
Shielding and survey instrument available
Contamination and radiation dose rate survey

52. Where Will Isotopes be Found?
In labs labeled with “Caution Radioactive Material” signs at the entrance
Usually stored in freezers, refrigerators, or fume hoods
Waste stored in labeled containers
Radioactive waste storage rooms

53. Postings and Labels Entrance to laboratory Refrigerator/freezer
Equipment/instruments
Radioactive waste containers
Laboratory benches
Fume hoods for use

54. Labeling Containers
All containers used for storing radioactive material or radioactive waste must be stored in labeled containers
The label displays the radiation symbol with the words “Caution Radioactive Material”
The isotope, activity in uCi or mCi and the start date should be included on label

55. Lesson 9 Radiation Detection

56. Detecting Radiation and Contamination
Personal dosimeters are used to detect the occupational exposure to employees from external sources of radiation
A survey meter may be used to detect large quantities of high energy beta and gamma emitters on a surface
For smaller quantities of contamination on surfaces and low energy beta emitters, use the wipe test method

57. Film Badge
Required when there is a possibility of receiving greater than 10% of exposure limit
Monitors for gamma, x-ray and high energy beta
Worn for 2 months
These are individual specific - Do not loan out
Return promptly after receiving a new one

58. Ring Dosimeter Monitors exposure to the hands
Used for high energy beta, gamma and x-ray radiation
Worn when handling sources like those listed above or x-ray machines

59. Survey Instruments Geiger Mueller (G-M)
- Detects alpha, beta, and gamma radiation
- Best option for detecting beta contamination
Sodium Iodide Detector
- Gamma and x-ray only

60. Survey Instruments Operational Check Check calibration date
Confirm calibration date within past year
Check batteries
Check response to radioactive source to confirm that the meter is operational

61. Survey Instruments Geiger-Mueller Detector Sodium-Iodine Detector
Used for beta, gamma and x-ray emitters
Best for P-32, S-35 and C-14
Will detect I-125 and Cr-51
Sodium-Iodine Detector
Detects gamma and x-ray emitters
I-125 and Cr-51
Do not use to detect beta emitters

62. Wipe Test Method
The Wipe Test Method is a means of monitoring for small amounts of contamination
It is the only method in the lab for detecting H-3
Wipe test surveys should include both areas where contamination is expected to be found and areas where it is not expected

63. Wipe Test Choose equipment and surfaces to wipe
Use a filter paper or Q-tip to wipe approximately 100 cm2.
Place filter paper or Q-tip in scintillation vial and add scintillation fluid (use enough fluid to fill at least ½ of vial)
Place sample in scintillation counter
Set scintillation counter to detect radioisotopes used in laboratory
Include a standard or sample containing a known amount of radioactive material
Include a background or control sample

64. Determining Activity of Wipes
If the scintillation counter only provides results in counts per minute (cpm) it will be necessary to convert those results to disintegrations per minute (dpm). This can be done by including a control sample with your wipes that contains the isotope of interest.
dpm = cpm / counting efficiency
Standard (cpm) / Standard (dpm) = Efficiency
1 uCi = 2.22 X 106 dpm
Decay of the standard’s activity must be considered.

65. Lesson 10 Contamination Control

66. Contamination
Definition: Radioactive material in an undesired location
Undesired
locations: Surfaces, skin, internal, airborne
Types: Removable – Decontamination is possible
Fixed – Unable to decontaminate

67. Contamination Limits <20 dpm/100cm2 a in restricted areas
<1,000 dpm/100cm2 b/g in restricted areas (radioisotope laboratories)
>1,000 dpm/100cm2 b/g immediately clean up to below 1,000 dpm/100cm2

68. Frequently Contaminated Items in Laboratories
Radioactive containers (stock, flasks, beakers)
Laboratory benches and sinks
Laboratory apparatus and equipment
(Centrifuge, Freezer, Waterbath)
Radioactive waste containers
Refrigerator door handles
Laboratory door handles
Gloves and laboratory coats

69. Contamination Control
Work in areas designated for radioactive material
Use absorbent pads
Wear appropriate protective clothing
Change gloves frequently
Perform a dry run of the procedure without radioactive materials
It is recommend that you set up well-defined, clearly labeled radioactive material work stations and restrict radioactive materials use to those areas

70. Spill Response Notify people working in the laboratory
Control access to the affected area
Wear gloves, lab coat, and safety glasses
Clean spill from the outer perimeter inward
Avoid spattering and generating aerosols
After initial clean up, monitor for contamination
Repeat process if contamination remains
Call the RSO (1-5037) if you need help or if the spill is greater than 100 µCi

71. Decontamination of Skin
If the radioactive material is a high energy beta, gamma, or x-ray emitter, monitor with a survey meter and record reading
Gently wash the affected area for 15 minutes with lukewarm water and a mild soap
If you continue to find contamination, repeat washing and monitoring for up to 3 times
Record final survey meter readings
Contact Radiation Safety at

72. Lesson 11 Obtaining Radioactive Materials

73. Ordering Radioactive Material
Orders are placed electronically through Buy ND
All orders must be approved by the Radiation Safety Office
When purchasing radioactive material from a vendor provide the following:
The Radioisotope
Amount of material
Name and phone number of P.I.
All packages must be addressed to Central Receiving/100 Mason Services
attn: Risk Management and Safety

74. Receiving Radioactive Material
Check Contents
Check box for contamination using a Geiger counter or wipe test.
Confirm that content of package is not contaminated.
If it is contaminated contact Safety.
Deface or remove any radiation labels on the box and discard as regular waste.
Ordering
Typically, orders arrive the following day
Ensure that somebody is available to pick up the Package
Wear lab coat and dosimeter to pick up package
Sign receipt log prior to leaving Safety

75. Receiving Radioactive Material
Checking package for contamination (Left)
Defacing labels (Right)

76. Lesson 12 Radioactive Waste

77. Radioactive Waste Disposal
Minimize generation of waste
Identify and segregate dry solid waste
- long lived (H-3 and C-14)
- - short lived (P-32 and S-35)
Complete a waste form for pickup
Keep disposal records

78. Do Not Mix Waste Types
Do not place scintillation vials into dry solid waste containers
Do not place dry solid waste into liquid scintillation vial waste
Do not place liquid waste container into dry solid waste containers
DO NOT MIX LONG AND SHORT HALF-LIVED WASTE (Break point = 89 days)

79. Holding Radioactive Waste for Decay
Provide appropriate shielding for the waste
Seal the container to prevent individuals from adding to the waste
Label the waste container with the isotope, amount of radioactive material, and date the container was sealed
Hold for 10 half-lives. This will be done by RMS.

80. Radioactive Waste Containers
DO NOT dispose of radioactive waste in:
- medical waste
containers
- general waste
Use only approved radioactive waste containers supplied by Radiation Safety which contains a warning label “Caution Radioactive Material”

81. Scintillation Vials
Place in a separate container from the dry solid radioactive waste
Separate scintillation vials containing long lived isotopes
(H-3 and C-14) from those containing shorter lived isotopes (P-32, I-125)
Ensure the lids are secured tightly on the bottles
Do not overfill the container
Complete a Radioactive Waste Form

82. Contaminated Sharps Syringes Pasteur Pipettes Scalpel Needles
Radioactive sharps must be segregated from other radioactive waste and placed in a radioactive materials labeled sharps container.

83. Collecting Liquid Use a durable carboy from RMS
Attach a radiation warning label to the bottle
Document the isotope, activity and date on the container
Secure the lid on the container at all times
NEVER POUR IT DOWN THE LAB SINK

84. Lesson 13 Clearing Equipment

85. Clearing Equipment For repair by Engineering or Vendor:
Ensure equipment is empty of all samples, containers, and radioactive material
Conduct wipe test and present results to RSO
Monitor with survey meter
Decontaminate equipment if required

86. Lesson 14 Review

87. When Working with Low Energy Beta Emitters
Examples: H-3, C-14, S-35, P-33
Follow General Safety Requirements
Use a GM survey meter for large quantities of C-14, S-35 and P-33
Isolate, label, and dispose of waste
Secure material in refrigerator/freezer

88. When Working with High Energy Beta Emitters (P-32)
Use Plexiglas shielding for storage
Wear Luxel dosimeter and extremity dosimeters if required
Handle material behind a Plexiglas shield
Regularly monitor work area and gloves for contamination
Use a GM detector or liquid scintillation counter

89. Working with Gamma or X-ray Emitters (I-125)
Store in leaded containers
Pre-experiment thyroid scan for work with large quantities or volatile forms of I-125
Wear Luxel dosimeter and extremity dosimeters if required
Use leaded glass/Plexiglas shield
Regularly monitor surfaces gloves
Use NaI detector or liquid scintillation counter
Post experiment thyroid scan for work with large quantities or volatile forms of I-125

90. Telephone Numbers Radiation Safety: 1-5037 Fax: 1-8794
Risk Management & Safety website:
After hours, weekends, holidays: Call ND Security