NRS Radiation Safety for Nursing

1. presented by
Radiology Training Associates
Instructor
E. Hooper

2. Give you tools to work safely with
radioactive materials
More than just checking a box, my hope is
that you actually get something out of this
that you can put to use in your daily
practice

3.  Types of Radiation
 Radiation Dose & Biological Effects
 Occupational Dose Limits
 ALARA Philosophy
 NRC Regulations, Inspections, & Licensure
 Workers Rights
 Safe Use of Radioactive Materials
 Signage & Postings

4. Transfer of energy through space
Radiation can be ionizing or non-ionizing
• Non-ionizing – MRI, Microwaves, Lasers, Radar
• Ionizing radiation can knock electrons off of an
atom
 Principle concern in Nuclear Medicine, X-Ray,
Fluoroscopy, and CT

5.  Alpha Particles (α)
• Short range (0.5 cm in air), easily shielded
• Ra-223 (Xofigo)
 Beta Particles (β
-
or β
+
)
• Tortuous path, best shielded with plastic
• Range ~ 10 ft/MeV in air; 0.5 cm/MeV in tissue
• Y-90 Microspheres, I-131
 Gamma Rays (γ)
• Can travel significant distances – penetrating
• Best shielded with high Z materials
• Tc99m used in Nuclear Medicine
 X-rays
• Byproduct of bremsstrahlung

6. Computed Tomography
24%
Nuclear Medicine
12%
Interventional Fluoroscopy
7%
Conventional Radiography
5%
Consumer
2%
Occupational
0%
Industrial
0%
Radon & Thoron
37%
Space
5%
Internal
5%
Terrestrial
3%
Data from NCRP Report 160
Background – 310 mrem
Medical – 300 mrem

7. Dose is defined as the energy deposited
per unit mass
• 1 J/kg = 1 Gray
Measured in units of
• Gy  absorbed dose
• Sv  dose equivalent
• 100 rad = 1 Gy
• 100 rem = 1 Sv
1 kg
Incident
Radiation
1.6 x 10-19 Joules = 1 eV

8. Non-stochastic effects (non-probabilistic)
• A threshold dose exists!
• Erythema
• Epilation
• Dermal Necrosis
Stochastic effects (probabilistic)
• A threshold does (might) not exist - LNT
• Most common stochastic effect – cancer
• Stochastic effects have a latency period
 Most cancers ~ 20 – 40 yrs

9.  Indirect Damage vs.
Direct Damage
• SSB vs. DSB
 3 stages to forming
cancer
• Initiator – mutational event
• Promoter – functional change
• Progression – tumor invasion
 Radiation is a weak
carcinogen because it
acts only as an
initiator.
H20
Incident
Radiation
Incident
Radiation
Free
Radical

10. Annual Limit
Whole Body (TEDE) 5,000 mrem 50 mSv
Extremities & Skin (SDE) 50,000 mrem 500 mSv
Lens of Eye 15,000 mrem 150 mSv
Gestational Limit
Declared Pregnant Workers 500 mrem 5 mSv
Limits
Members of the Public 100 mrem* 2 mrem in any 1 hour
* Limit goes to 500 mrem when source is an individual administered unsealed byproduct material

11. As Low As Reasonably Achievable
• Reasonable efforts should be made to keep
occupational doses as far below regulatory limits
as possible
Fundamentals of radiation protection
• Time, Distance, & Shielding
Sources of exposure in nuclear medicine
• Sealed sources, unsealed RAM (doses), patients,
CT
• Dose rate at 1 m from a patient injected with 20
mCi of 99m
Tc is ~ 1 mrem/hr

12. 1 R
2 R
3 R

13. Some considerations
• What types of radiation are you shielding?
• What is the energy and activity?
• What shielding material do you have available?
Useful shields in Nuclear Medicine
• Syringe shields, leaded carrying boxes, pigs, lead
bricks, L – blocks, other people
Shielding should be placed as close to the
source as possible
• Isotropic vs. collimated beam

14. Nuclear Regulatory Commission
• Radioactive Materials Licensure
 Who, What, Where, How & License Conditions
• 10 CFR
 19 – Notices, Instructions & Reports to Workers
 20 – Standards For Protection Against Radiation
 30 – Rules of General Applicability to Domestic
Licensing of Byproduct Material
 35 – Medical Use of Byproduct Material
• NUREG 1556 Vol. 9, Rev. 2
• Inspections
www.nrc.gov

16. Applicable to individuals likely to receive
more than 100 mrem
Instructed in general radiation safety
Instructed in responsibility to report to
licensee unsafe conditions or unnecessary
exposures
Advised of dosimetry results

18.  Wear gloves, labcoats, & other
PPE (bench coats)
 Monitor for contamination
 Use syringe shields
 Do not eat, drink, or store food
in use areas
 Wear dosimeters
 Dispose of radioactive waste
appropriately
 Never pipette by mouth
 Perform weekly wipe tests
 Perform daily surveys (written
directives)
 Store radioactive materials in
labeled & shielded containers
 Label vials and syringes
 Assay doses in a dose
calibrator
 Doses should be within ±20%
 Check patients name and ID
before administering
 Secure radioactive materials
from unauthorized removal

19. Caution, Radioactive Materials
• Rooms & Containers
• Exempt if less than 8 hrs
Caution, Radiation Area
• ~ 5mR/hr @ 30cm
Part 19, Part 20, RAM License, Operating
Procedures, & Notice of Violations
• May post a notice where documents can be found
NRC Form 3