Radiation Safety Flashcards
1
Q
QC Numbers Must Be Within: (%)
A. Centering:
B. Distance:
C. Collimation:
D. Exposure Time:
E. kVp Calibration:
F. Exposure Reproducibility:
G. Exposure Linearity:
A
A. Centering: 1%
B. Distance: 2%
C. Collimation: 2%
D. Exposure Time: 5%
E. kVp Calibration: 5%
F. Exposure Reproducibility: 5%
G. Exposure Linearity: 10%
2
Q
- Ionization results in: _______ & ________
- Explain Indirect Effects Occur:
- What can happen when DNA is damaged?
A.
B.
C.
A
- Free electrons that are Negative & Positive Charged atom
- Photon interacts with water of cell
- results in radiolysis
- radiolysis creates free radicles and hydrogen peroxide that causes damage - Base Pair Lesions, Single Stand Breaks & Double Strand Breaks
3
Q
- What is Radiolysis?
- What does this create?
- Which DNA damage is repairable?
- which is not? - Which DNA damage results in cell death or mutation?
A
- Ionization of water molecule
- Creates free radicals / hydrogen peroxide
- Base Pair Lesion
- Double Strand Break - Double Stand Break
4
Q
- What is Stochastic Effect of Radiation?
- Relation to Dose/Severity?
- Response Curve &Threshold?
- Examples:
A
- Random, Unpredictable, Probability
- Probability of effect occuring increases with exposure but severity is NOT affected by dose
- (Cancer isn’t worse b/c dose larger) - Linear, Non-Threshold
- Ex: Cancer & Genetic Mutations
5
Q
- What is Deterministic Effect of Radiation?
- Relation to Dose/Severity?
- Response Curve &Threshold?
- Examples:
A
- Predictable
- Effects occur at specific dose threshold
- Linear, Threshold
- Ex: Decreased sperm count, erythema, epilation, skin cancer
6
Q
- Linear Non-Threshold Dose Response Model states:
- Thresholds for:
A. Decrease Sperm Count:
B. Erythema:
C. Epilation: - These are all examples of:
A
- No safe dose, any dose could cause cancer
- A. Decrease Sperm Count: 150 mGy
B. Erythema: 2,000 mGy
C. Epilation: 3,000 mGy - Deterministic
7
Q
- When do short-term effects occur?
- Deterministic or Stochastic?
- Response Model: - Examples:
- Other Name(s) for short-term effects:
A
- Within minutes-hours after exposure
- Deterministic
- Threshold, Predictable - Erythema, Temporary sterility, ARS
- Immediate / Early Effects
8
Q
- When do long-term effects occur?
- Deterministic or Stochastic?
- Response Model: - Examples:
- Other Name(s) for short-term effects:
A
- Several years after exposure
- Stochastic
- Non-Threshold, Probabilistic - Cancer, Mutations
- Delayed Effects
9
Q
- What is latent period?
- Cataracts is a _________ effect,
but is ______ (Stochastic or Deterministic)
Meaning it ______ (does or does not) have a threshold dose. It occurs ______ after exposure. - Latent period for Leukemia is ______, making it an example of _______.
- Latent period for Thyroid, Breast, Lung & Bone are ______, making them an example of _______.
A
- Time between “infection” and signs of symptoms
- Cataracts = Long-Term Effect
- Deterministic
- Has Threshold
- Occurs several years later - Leuk. 5-7 years = LONG TERM
- 10-60 years = LONG TERM
10
Q
- Somatic Effects of Radiation cause harm to _______.
- Do these effects pass on?
- Examples:
A
- Harm to body of person exposed
- SOMA = Body - Damage is not passed on
- Cancer, Cataracts, fetal/embryo effects**
(**because radiation occurs to fetus / it is not passed on from genetics)
11
Q
- Genetic Effects of Radiation cause harm to _______.
- Do these effects pass on?
- Examples:
A
- Harm passed on to future generations (not to exposed) through reproductive organs
- Harm to reproductive germ cells (sperm & ova) - DNA damage is passed on
- Mutation, Cystic Fibrosis, Heart Disease
12
Q
- Why is fetus/embryo effects somatic?
- What is ARS?
- Short or long term? - What are 3 possible effects of reproductive organs when exposed to radiation?
A
- Somatic because fetus/embryo is being exposed to radiation at the time, it is not being passed through germ cells
- Acute Radiation Syndrome occurs from extremely high whole-body exposures
- Short-Term - Cancer (Carcinogenesis),
Infertility
Genetic Effects
13
Q
- Explain Doubling Dose:
- What is the approximate value:
- Explain Genetically Significant Dose (GSD):
- Average GSD from medical imaging:
A
- Hypothetical dose required to double rate of genetic disease that already naturally occur in human population
- 1.5 Sv
- Actual estimate of real dose to gonads of reproductively active population
- (Estimates total dose that could cause genetic diseases) - 0.3 mSv
14
Q
- What are the reproductive cells?
- Acute Radiation Syndrome is a result of:
- Example: - ARS is ________ (Stochastic or Deterministic)
Meaning it ______ (does or does not) have a threshold dose. It occurs ______ after exposure. - Acute Radiation Syndrome often results in:
A
- Sperm & egg/ova
- High Dose to Whole-Body
- Nuclear Accident - Deterministic (Predictable)
- Has threshold (Occur at specific dose)
- Early Effect (Occurs soon after exposure, minutes/hours/days) - Death due to body system failure/responses
15
Q
- What are three systems mainly effected in Acute Radiation Syndrome?
- What is LD50/30?
- What is ARS’s LD?
A
- Hematopoietic
- Gastrointestinal
- Cerebrovascular - Lethal Dose that will kill 50% of population within 30 days
- ARS is LD 50/60 (3-4Gy)
16
Q
- In ARS, Hematopoietic Syndrome begins occurring at doses ______, causing _______.
- Symptoms include: ____. ______& _______
- Death Time Frame:
- Caused By:
- Survival Possibility:
A
- Greater than 1 Gy, causing blood cell death
- Anorexia, Fever, Lethargy
- Within 1-2 months
- Infection or Hemorrhage - Some may
17
Q
- In ARS, Gastrointestinal Syndrome begins occurring at doses ______, causing _______.
- Symptoms include: ____. ______& _______
- Death Time Frame:
- Caused By:
- Survival Possibility:
A
- Greater than 1- Gy, causing destruction of GI tract
- Diarrhea, dehydration & electrolyte imbalance
- 9-10 days
- Dehydration - Not expected to survive
18
Q
- In ARS, Cerebrovascular Syndrome begins occurring at doses ______
- Symptoms include: ______& _______
- Death Time Frame:
- Caused By:
- Survival Possibility:
A
- Greater than 50 mGy
- Convulsing & Coma
- Within Hours / Most Severe Response
- Unknown specific cause - No survival
19
Q
- Which ARS response occurs at 1 Gy?
- Which ARS response symptoms are diarrhea and dehydration?
- Which ARS response occurs at 10 Gy?
- Which ARS response is most severe?
- What is its response dose?
A
- Hematopoietic
- GI
- GI
- Cerebrovascular
- 50 mGy