rad_protection Flashcards
Def of radiation
Energy traveling through space emitting radiant energy in the form of waves or particles.
Def of ionization
Process by which neutral atoms acquires a pos or neg charge
Ionizing radiation
Produces negatively and positively charged particles as it passes through matter
ALARA
As Low As Reasonably Achievable
What agency set the first rad protection standards
International Commission on Radiological Protection (ICRP)
What agency was established in the US and is the primary standard setter
National Council on Radiation Protection and Measurement (NCRP)
Agency that regulates the safe use of “reacted produced” radio active materials in medicine and no medical practices
Nuclear Regulatory Commission (NRC)
Agency that regulates naturally occurring radioactive materials such as radon and radium
NRC
Agency that regulates x-ray machines (including LINACs)
Individual States
If you decrease your time by 1/2, you decrease your exposure by _____
2
If you increase your distance by 2, you decrease your exposure by ____
4
If you increase your shielding by 1 HVL, you decrease your exposure by ____
2
What is CFR
Code Federal Regulation
List steps for a bracy Source Receipt:
- Inspect Package and Labels (transport index - dose rate at 1 meter)
- Survey Outside of Package
- Swipe for contamination ouside of package and pigs
- Log sources into Inventory Book
For a Source Receipt, what are the limits when surveying the outside of the package?
- Prostate Seeds < 2 mR/hr on surface
- HDR Source < 2 mR/hr at 1 meter
**ion chamber survey meter is used
For a Source Receipt, what are the limits when swiping for contamination outside of package and pig, and what is used for the survey?
- < 2000 dpm (disentegration per minute)
- Well Chamber Counter
Do Prostate Seeds or HDR sources require leaks tests during a Source Receipt?
No
Steps for Source Strength Calibration:
- Re-entrant Chamber
- Sample 10% of Prostate Seeds
- Calibrate the HDR Source
- Agreement to within 5%
Explain Sealed Source Inventory / Leak Test
- Inventory every 3 months
- SS Leak tests every 6 months
- Leak Tests: < 0.005 uCi
What is a Written Directive
An authorized user’s written order for the admnistration of material or radiation to a patient
Who is considered an Authorized User?
Physician
Along with the patients name, what must be included in the Written Directive for various types of radiation tx?
For:
- NaI I-131 with doses > 30 uCi: dosage
- Therapy dose other than I-131: dosage, radioactive drug, and method of delivery
- Manual Brachy, LDR: Before tx - Tx site, radionuclide, dose; after tx - tx site, radionuclide, total dose (exposure time), and # of sources
- Gamma Knife: tx site, total dose, values for the target coordinate setting
- HDR: tx site, dose/fx, # of fx, total dose, radionuclide
- Teletherapy: tx site, dose/fx, # of fx, total dose
What is considered a Medical Event:
- Total dose delivered differs from Rx by 20% or more
- Fractionated dose delivered differs from Rx, for a single fx, by 50% or more
- A does that exceeds 5 rem effective dose equivalent
- A dose that exceeds 50 rem to an organ or tissue, or shallow dose equivalent to the skin from: wrong radionuclide, wrong route, wrong pt, wrong mode, and/or leaking source
- Dose to skin, organ, or tissue other than tx site exceeding 50 rem and 50% of expected Rx
How to report a Medical Event:
- Telephone to NRC within 1 day of discovery
- Written Report to NRC within 15 days
- Written notice to MD within 24 hrs
- Written notice to pt within 24 hrs
*do not need to tell pt before MD, not required to notify pt if MD agrees to do so, or if MD decides info will harm pts well-being based on medical judgement
What is the Occupancy Factor for “Full Occupancy Areas”:
T = 1.0
Define Full Occupancy Area, and what areas are considered Full Occupancy?
areas occupied full-time by an individual;
- tx palnning areas
- tx control rooms
- nurse stations
- receptionist areas
- attended waiting rooms
- occupied space in nearby building
What is areas have an occupancy factor of 1/2?
Adjacent tx room, pt examination room adjacent to shielded vault
What is areas have an occupancy factor of 1/5?
Corridors, empolyee lounges, staff rest rooms
What is areas have an occupancy factor of 1/8?
Tx Vault doors
What is areas have an occupancy factor of 1/20?
Public toilets, unattended vending rooms, storage areas, outdoor areas with seating, unattended waiting rooms, patient holding areas, attics, janitors closets
What is areas have an occupancy factor of 1/40?
Outdoor areas with only transient pedestrain or vehicular traffic, unattended parking lots, vehicular dop off areas, stariways, unattended elevators
