Deck 11: Radiobiology and Radiation Safety

Question 1

What is erythema?

A) Loss of hair caused by a high-radiation dose
B) Loss of hair caused by long-term, low-radiation dose
C) Reddening of the skin caused by high-radiation dose
D) Reddening of the skin caused by long-term, low-radiation dose

Answer 1

Reddening of the skin caused by high-radiation dose

Question 2

At what whole body equivalent dose will blood changes be seen?

A) 0.25 Sv
B) 1.5 Sv
C) 2.0 Sv
D) 2.5 Sv

Answer 2

0.25 Sv

Question 3

Patient doses in radiography are usually calculated as the:

A) air kerma (Gy-a).
B) cumulative dose (Gy-t).
C) absorbed dose (Gy-t).
D) entrance skin exposure (ESE).

Answer 3

entrance skin exposure (ESE).

Question 4

According to the Law of Bergonie and Tribondeau,which of the following groups would not be as sensitive to radiation?

A) Fetuses
B) Infants
C) Children
D) Adults

Question 5

Which of the following cells would not be as vulnerable to x-rays?

A) Thyroid cells
B) Skin cells
C) Nerve cells
D) Blood cells

Question 6

Short-term effects of radiation would occur within how long?

A) 3 months
B) 1 year
C) 10 to 15 years
D) 5 to 30 years

Question 7

According to the Law of Bergonie and Tribondeau,which of the following types of cells are very radiosensitive?

A) Nerve and muscle
B) Blood and blood-producing
C) Cortical bone
D) Glandular

Question 8

The unit of the SI system used to measure the equivalent dose is the:

A) roentgen (R).
B) sievert (Sv).
C) gray (Gy-t).
D) air kerma (Gy-a).

Question 9

To ensure the lifetime risk of occupationally exposed persons remains within acceptable limits,each person cannot exceed a lifetime dose. The lifetime dose is termed the ______ dose.

A) absorbed
B) equivalent
C) effective
D) cumulative effective

Question 10

The SI unit for measuring absorbed dose is the:

A) air kerma (Gy-a).
B) sievert (Sv).
C) gray (Gy-a).
D) roentgen (R).

Question 11

In radiography,patient dose is usually calculated:

A) within the organ.
B) at the exit organ.
C) as an average of the entrance and exit exposure.
D) at the skin level.

Question 12

What is the guiding philosophy of radiation protection?

A) ALARMA-as long as radiographs are made accessible
B) ALARA-as low as reasonably achievable
C) ALAIS-as long as ionizations are small
D) ALAP-as low as possible

Question 13

Which of the following radiation values will always be an equal dose in diagnostic radiology?

A) Absorbed dose and exposure
B) Absorbed dose and equivalent dose
C) Absorbed dose and effective dose
D) Absorbed dose and cumulative effective dose

Question 14

The unit commonly used to report the effective dose to occupational workers in the United States is:

A) R.
B) mGy (old mrad).
C) mSv (old mrem).
D) mR.

Question 15

At what whole-body equivalent dose will death occur?

A) 1.5 Sv
B) 2.0 Sv
C) 3.0 Sv
D) 6.0 Sv

Question 16

Which of the following radiographic examinations typically delivers the greatest gonadal exposure?

A) Chest
B) Pelvis
C) Skull
D) Limb

Question 17

The radiation weighting factor for x-ray photons is which of the following?

A) 1
B) 2
C) 20
D) 25

Question 18

Short-term effects of radiation would occur at absorbed doses greater than which of the following?

A) 50 mGy-t
B) 100 mGy-t
C) 200 mGy-t
D) 500 mGy-t

Question 19

What is the SI unit of exposure that measures radiation in air?

A) Gray (Gy-a)
B) Sievert (Sv)
C) Rad (rad)
D) Air kerma (Gy-a)

Question 20

Which of the following is measured based on the type and energy of the radiation exposed to?

A) Exposure
B) Absorbed dose
C) Equivalent dose
D) Effective dose

Question 21

Which of the radiographic examinations listed would give the fetus the highest "fetal dose"?

A) Chest
B) Cervical spine
C) Lumbar spine
D) Skull

Question 22

A common and observable short-term effect of radiation is:

A) erythema.
B) mutations.
C) leukemia.
D) carcinogenesis.

Question 23

The greatest percentage of long-term effects from radiation exposure will occur at:

A) 3 months.
B) 5 years.
C) 10 to 15 years.
D) 5 to 30 years.

Question 24

The greatest cause of unnecessary radiation to patients is from:

A) repeat exposures.
B) CT scans.
C) radon gas.
D) chest x-rays.

Question 25

The lead-equivalent thickness of a gonad shield should be _____ mm.

A) 0.3
B) 0.5
C) 1.0
D) 1.5

Question 26

A gonad shield should be used whenever the edge of the radiation field is within ________ cm of the gonads.

A) 3
B) 5
C) 6
D) 8

Question 27

Which of the following would be used to reduce the likelihood of genetic radiation effects?

A) SID greater than 40 inches
B) Low mAs
C) Low kVp
D) Gonad shields

Question 28

In general,which radiation effect are we most concerned about?

A) Short-term
B) Long-term
C) Somatic
D) Genetic

Question 29

Which of the following changes decrease the dose to the limited operator?
1) Minimize the time spent in the radiation area.
2) Increase the distance between the operator and the source of radiation.
3) Use shielding-control booth and lead apparel.

A) 1 and 2 only
B) 1 and 3 only
C) 2 and 3 only
D) 1, 2, and 3

Question 30

The EDE limit for whole-body dose of occupational radiation exposure for nonpregnant workers older than age 18 who are involved in radiation use is _____ per year.

A) 1.25 rem
B) 5.0 mrem
C) 0.5 rem
D) 5.0 rem

Question 31

Which of the following effects of radiation exposure are predictable?

A) Short-term
B) Long-term
C) Somatic
D) Genetic

Question 32

Which of the following can the limited operator do to keep radiation exposure to patients as low as reasonably achievable?
1) Use a small radiation field.
2) Use the highest kVp possible.
3) Never use an SID below 40-in.

A) 1 and 2
B) 1 and 3
C) 2 and 3
D) 1, 2, and 3

Question 33

Which of the following would be considered long-term effects of radiation exposure?
1) Cataracts
2) Leukemia
3) Erythema

A) 1 and 2
B) 1 and 3
C) 2 and 3
D) 1, 2, and 3

Question 34

Radiation exposure to the gonads can cause changes in the genes of the irradiated person called:

A) mitotic rate.
B) mutations.
C) short-term effects.
D) long-term effects.

Question 35

The lethal dose of radiation is expressed as the:

A) ESE 50.
B) ESE 100.
C) LD 50/60.
D) LD 50/30.

Question 36

When radiation exposure occurs during pregnancy,the greatest risk of birth defects occurs when the exposure:
1) to the uterus exceeds 5 rad.
2) occurs within the first trimester of pregnancy.
3) occurs within the third trimester of pregnancy.

A) 1 and 2 only
B) 1 and 3 only
C) 2 and 3 only
D) 1, 2, and 3

Question 37

The federal regulation for the lead-equivalency of aprons that are worn in the radiographic room is _____ mm.

A) 0.10
B) 0.25
C) 0.5
D) 1.0

Question 38

Which of the following would not be a mutation as a result of radiation to the gonads?

A) Cleft palate
B) Spina bifida
C) Polydactyly
D) Leukemia

Question 39

Today,the average American is exposed to how much of an annual radiation dose?

A) 3.6 mSv
B) 5.0 mSv
C) 6.3 mSv
D) 7.0 mSv

Question 40

The federal regulation for the lead-equivalency of gloves worn during radiographic procedures is _____ mm.

A) 0.10
B) 0.25
C) 0.50
D) 1.0

Question 41

The NCRP recommended monthly equivalent dose limit for a pregnant worker is _____ mSv.

A) 0.25
B) 0.5
C) 0.7
D) 0.9

Question 42

A personnel monitor cannot measure exposures less than _____ mSv.

A) 0.025
B) 0.05
C) 0.50
D) 1.0

Question 43

The greatest risk for a pregnant women who receives a high exposure is during the:

A) first trimester.
B) second trimester.
C) third trimester.
D) first 3 weeks.

Question 44

A 28-year-old radiation worker can have an annual cumulative effective dose of:

A) 28 Sv
B) 280 Sv
C) 28 mSv
D) 280 mSv

Question 45

According to the NCRP,there is cause for concern if a pregnant woman receives a dose in excess of ______ to the uterus.

A) 15 Gy-t
B) 25 Gy-t
C) 150 mGy-t
D) 250 mGy-t

Question 46

Which national organization prepares the standards for radiation dose limits of occupational radiation workers?

A) National Council on Radiation Protection
B) American Society of Radiologic Technologists
C) The Joint Commission
D) American Registry of Radiologic Technologists

Question 47

Personnel monitors should be worn:
1) in the region of the collar.
2) on the anterior surface of the body.
3) outside the apron.

A) 1 and 2
B) 1 and 3
C) 2 and 3
D) 1, 2, and 3

Question 48

Personnel monitors should be worn whenever radiation workers are likely to risk receiving ____% or more of the annual effective dose limit.

A) 5
B) 8
C) 10
D) 15

Question 49

The NCRP recommended 9-month equivalent dose limit for a pregnant worker is _____ mSv.

A) 0.25
B) 0.5
C) 2.5
D) 5

Question 50

The most widely used and most accurate personnel monitor is the:

A) visual dosimeter.
B) film badge.
C) thermoluminescent dosimeter (TLD).
D) optically stimulated luminescence (OSL).

Question 51

A declared pregnant radiation worker should wear a second personnel monitor. This monitor should be positioned at the:

A) collar.
B) waist level.
C) sleeve closest to the radiation.
D) the sleeve farthest from the radiation.

Question 52

The annual effective dose limit for an occupational radiation worker is:

A) 25 mSv
B) 50 mSv
C) 1 Sv
D) 5 Sv