1. Radiation Safety Refresher Training
Radiation Safety Program
University of Wisconsin - Milwaukee

2. Properties of Radiation
Radioactivity is the natural property of certain nuclides to spontaneously emit energy, in form of ionizing radiation, in an attempt to become more stable.
Ionizing radiation has the ability to remove electrons from atoms, creating ions. Ionization is the product of negatively charged free electrons and positively charged ionized atoms

3. 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 used at UWM include:
Particulate Radiation
Alpha
Beta
Photon Radiation
Gamma
X-Ray

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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

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

13. 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 remaining
If you wait 28.6 days, you will only have 62.5 µCi remaining
Shipment After 14.3 days After 28.6 days

14. Example of Half Life
It is important to consider the half life of the radioisotope when planning a study that includes the use of radioactive materials

15. ALARA
Primary goal of radiation safety is to avoid any unnecessary radiation exposure and to keep all exposure As Low Reasonably Achievable

16. aLARA
Reducing the dose from any source radiation exposure involves the use of three protective measures:
TIME
DISTANCE
SHIELDING

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

18. 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

19. Shielding
To shield against beta emissions, use plexiglass to decrease the production of bremsstrahlung radiation.
To shield against gamma and x-rays, use lead, leaded glass or leaded plastic

20. Internal Exposure
Only a few commonly used radionuclides at UWM 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

21. Minimizing Internal Exposure
Good lab practices will help minimize the chance of contamination.
Wear personal protective equipment
If required, use a fume hood when working with volatile substances in a certified hood
No eating, drinking or applying cosmetics
Clean up spills promptly
Routinely monitor work area
Secure radioactive material

22. Personal Protective Equipment (PPE)
Using PPE along with time, distance, and shielding will ensure that exposure is kept as low as reasonably achievable (ALARA).
Laboratory coat
Gloves
Safety Glasses
Dosimeters
Close-toed shoes
Full length pants

23. Dosimeter
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 3 months
These are individual specific - Do not loan out
Return promptly after receiving a new one
Exposure reports are provided annually or at your request

24. Ring Dosimeter Monitors exposure to the hands
Used for high energy beta, gamma and x-ray radiation
Worn when handling > 500 µCi of P-32 or high energy gamma emitters

25. Safe handling of radioactive materials
When working with radioactive materials, users should:
Prepare your radioactive materials work area in the lab
Cover work area with absorbent paper
Set up radiation shields
Ensure that radioactive waste containers are available
Turn on survey meter and place adjacent to work area

26. Safe handling of radioactive materials
Survey radioactive material work areas before, during, and after handling
Survey common areas and frequently touched objects such as desk areas, computer keyboards, mice, door knobs and light switches
Perform personal contamination surveys
Scan gloves frequently during experiments
Monitor whole body before leaving laboratory

27. Survey Instruments Geiger-Mueller 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

28. 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

29. 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
Place clean up materials in appropriate radiation waste container
After initial clean up, monitor for contamination
Repeat process if contamination remains
Call Radiation Safety ( ) if you need help, if the spill is greater than 100 µCi or the spill is in a public area
Document the spill, contact Radiation Safety
Spill kits are located in all radioactive labs
Notify Radiation Safety of any conditions or practice that you think may be unsafe

30. 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

31. Radioactive Materials License
UWM has a Limited Scope Academic License
All requests for use of new radionuclides or to become a new Authorized User should be submitted to the Radiation Safety Department at UWM.
Rad Safety will then submit that information to the Department of Health Services (DHS) for approval.
Approvals from DHS may take 3-4 weeks.

32. Ordering Radioactive Material
All orders must be approved by Radiation Safety
Notify Radiation Safety when you plan to place an order. This will ensure that there is appropriate coverage to receive the package.
All radioactive material packages must be shipped to the Radiation Safety Office. That address is:
University of Wisconsin – Milwaukee
Attn: K. Axtman, Radiation Safety
3209 N. Maryland Avenue, Lapham Rm 181
Milwaukee, WI
Once received by the RSO the material will be surveyed and inventoried and then released to the laboratory

33. Radioactive Waste Disposal
Minimize generation of waste
Identify and segregate waste
- long term (H-3 and C-14)
- intermediate (S-35 and I-125)
- short lived (P-32)
Complete disposal forms and maintain with your lab records
Do not dispose radioactive waste down the drain.

34. Segregate your Radioactive Waste and do not mix with Hazardous Waste
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
Segregate your Radioactive Waste and do not mix with Hazardous Waste

35. 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”

36. 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 and contact Radiation Safety when container is full

37. 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.

38. When Working with Low Energy Beta Emitters
Examples: H-3, C-14, S-35, P-33
Have access to a liquid scintillation counter
Use a GM survey meter only for large quantities of C-14, S-35 and P-33
Isolate, label, and dispose of waste
Secure material when not in use

39. When Working with High Energy Beta Emitters (P-32)
Wear whole body dosimeter and extremity dosimeters if required
Handle material behind a Plexiglas shield
Regularly monitor work area and gloves for contamination
Isolate, label, and dispose of waste
Secure material when not in use
Use Plexiglas shielding for storage

40. Working with Gamma or X-ray Emitters
Minimize time handling material; use remote handling devices as necessary
Wear whole body dosimeter and extremity dosimeters if required
Regularly monitor work area and gloves for contamination
Isolate, label, and dispose of waste
Secure material when not in use
Store sources behind lead shielding

41. Security
Areas where radioactive materials are opened, used, or stored must either be locked, or be under constant surveillance by trained radiation workers.
If an inspector can, at any time, gain access to a radioactive materials lab and discover radioactive materials in any form, without being confronted and asked for identification, then a violation has occurred.

42. Security
Radioactive materials should be stored in locked refrigerators, freezers or storage units. If workers who are not trained and authorized to work with radioactive materials have access to the storage unit, the radioactive material should be stored in locking boxes that are secured.

43. BUT WAIT, THERE’S MORE… Training
This completes your ANNUAL Radiation Safety Refresher Training (quiz on next slide).
If you have any questions, please contact the Radiation Safety office at: or
University Safety and Assurances Office
University Safety and Assurances Website
BUT WAIT, THERE’S MORE…

44. Click here for RAD Safety QUIZ
Radiation Safety Quiz
To receive credit for this training, please complete the following short quiz…
Click here for RAD Safety QUIZ