Rad 260: Safety

Question 1

How do you calculate equivalent dose?

Answer 1

Absorbed dose (Gy) times the radiation weighting factor (Wr)

Question 2

How do you calculate Effective dose?

Answer 2

Absorbed dose times the radiation weighting factor times the tissue weight.

Question 3

What are the two types of cell damage that may occur from Ionizing radiation

Answer 3

Somatic or Genetic

Question 3

True or False: a production of low-energy x-rays can be a result of ionization in human cells?

Answer 3

True

Question 4

Define Primary Radiation

Answer 4

Radiation exiting the x-ray tube

Question 5

Define Exit Radiation

Answer 5

X-rays that emerge from the patient and strike the image receptor; composed of primary and scattered photons

Question 6

Define Attenuation

Answer 6

Absorption and scatter of the x-ray beam as it passes through the patient

Question 7

What is a Compton Interaction?

Answer 7

A x-ray photon strikes a loosely bound outer-shell electron and transfers part of its energy and ejecting is it from the shell. then continues to strike or move with less energy than before.

Question 8

Define coherent scatter

Answer 8

Produced by low-energy x-ray photons where electrons are not removed but vibrate emitting energy equal to the original

Question 9

Who publishes the annual dose limits?

Answer 9

NCRP

Question 10

What is linear-nonthreshold?

Answer 10

The degree of response is directly proportional to the amount of radiation received

Question 11

What is the annual effective dose limit for occupational exposure?

Answer 11

50mSv

Question 12

What is the annual effective dose limit for the general public?

Answer 12

1mSv

Question 13

What is the effective dose limit for the embryo or fetus for all of gestation?

Answer 13

5.0 mSv

Question 14

Erythema, Epilation, decreased blood count and acute radiation syndrome are all examples of …

Answer 14

Early tissue reactions

Question 15

Cataracts to form, thyroid cancer, and effect on fertility are all examples of…

Answer 15

Late tissue reactions

Question 16

Radiation-induced malignancy, nonmalignant radiodermatitis, Embryologic effects, and Genetic mutations are all examples of…

Answer 16

Stochastic effects

Question 17

A portion of the cellular life cycle that occurs before mitosis is…

Answer 17

Interphase

Question 18

somatic cell division, includes four phases.

Answer 18

Mitosis

Question 19

When mitosis is complete how many chromosomes does each new cell contain?

Answer 19

46

Question 20

When mitosis is complete how many chromosomes are in each germ cell?

Answer 20

The number of chromosomes halves in each cell

Question 21

What is Direct Effect?

Answer 21

When radiation transfers its energy directly to the DNA (the master molecule) or RNA.

Question 22

What is erroneous information passed to subsequent generations via cell division?

Answer 22

Mutation

Question 23

What is Indirect Effect?

Answer 23

When the radiation strikes the water in the cell and can cause radiolysis of water.

Question 24

True or False? Results of indirect effect include no effect, formation of free radicals and formation of H2O2.

Answer 24

True

Question 25

The amount of filtration that reduces the intensity of the x-ray beam to half of its original value is?

Answer 25

Half-value layer

Question 26

What is LIH and how does it help limit patient dose?

Answer 26

Last image hold allows the last image to display on the monitor without radiation exposure. Allowing the radiologist to evaluate an image without continued patient exposure.

Question 27

What is the most responsible for radiation exposure to t?he radiographer

Answer 27

Scatter radiation

Question 28

True or false? The x-ray tube housing prevents any excess leakage radiation.

Answer 28

False, x-rays may leak through the housing and we can not let it exceed 1mGy /hr