Exam 4 Ch 35- Health Physics

Question 1

health physics-

Answer 1

practice is providing radiation protection for workers & public

Question 2

health physics term was coined-

Answer 2

during manhattan project

Question 3

health physicists can be-

Answer 3

-physician
-engineer
-radiation scientist concerned w: the research, teaching, or operation aspects of radiation safety

Question 4

3 components to ALARA-

Answer 4

-1st 2 are medical provider
- each exam has to have a specific reason

Question 5

Radiation & health dose response relationship-

Answer 5

linear non-threshold

Question 6

4 types dose response curve-

Answer 6

threshold, non-threshold, linear, & non-linear

Question 7

dose response curve tells us-

Answer 7

there’s no safe dose

Question 8

as soon as dose response curve is possible-

Answer 8

no amt. of radiation is considered safe

Question 9

job of health physicist-

Answer 9

-design equipment
-calculate & construct barriers
-develop protocols in keeping w: ALARA,

Question 10

3 principles of radiation protection-

Answer 10

time, distance, & shielding

Question 11

ALARA is set in place for-

Answer 11

-pt. imaging
-protecting public & occupational workers

Question 12

cardinal rule for time-

Answer 12

minimize time (repeat exams)

Question 13

total patient dose is directly proportional to-

Answer 13

the amount of time the patient was exposed

Question 14

reducing time also reduces-

Answer 14

involuntary motion blurring

Question 15

during fluoro, the radiologist is responsible for-

Answer 15

reduction of time

Question 16

method that fluoroscopy uses to reduce time-

Answer 16

sequence on & off timer

Question 17

when keeping time to a minimum, ______ is used to maintain ALARA-

Answer 17

5 min. reset timer

Question 18

most effective in radiation protection-

Answer 18

distance

Question 19

want to _____ distance-

Answer 19

maximize

Question 20

when maximizing distance, the job of rad tech is-

Answer 20

stay as far from patient as practical

Question 21

as distance b/w person & source increase-

Answer 21

exposure to that person decreases rapidly

Question 22

2 sources in distance-

Answer 22

point source & extended source

Question 23

point source vs. extended source rule-

Answer 23

if the distance from the source is 5x greater than the source diameter, treat it as point source

Question 24

distance in radiography-

Answer 24

-SID is fixed
-tech is behind barrier (tech. dose should be 0)

Question 25

in fluoro, in relation to distance, the tech must practice-

Answer 25

good protective measures

Question 26

shielding-

Answer 26

barrier b/w source of radiation (tube) & patient

Question 27

Half Value Layer (HVL)-

Answer 27

amt of filtration material required to reduce intensity to 1/2 original value

Question 28

Tenth Value Layer (TVL)-

Answer 28

amt. of filtration material required to reduce intensity to 1/10 original value

Question 29

Effective dose-

Answer 29

radiation risk based on whole body dose

Question 30

effective does is the equivalent ____-

Answer 30

whole body dose following partial-body radiation exposure

Question 31

radiography uses _____ exposure-

Answer 31

collimated exposure

Question 32

stochastic radiation response proportional to-

Answer 32

effective dose

Question 33

stochastic results from-

Answer 33

low exposure & appears as late effects

Question 34

non-stochastic results from-

Answer 34

high exposure & appears as early response

Question 35

stochastic effects aka-

Answer 35

probabilistic

Question 36

stochastic effects-

Answer 36

chance of getting effect rather than severity of effect increases w: dose

Question 37

stochastic effects examples-

Answer 37

cancer, leukemia, genetic effects, & non-specific life span shortening

Question 38

Non-stochastic effects aka-

Answer 38

deterministics

Question 39

Non-stochastic effects-

Answer 39

severity of the effect rather than the chance of getting the effect increases w: dose

Question 40

Non-stochastic effects example-

Answer 40

skin erythema & acute radiation syndrome (ARS)

Question 41

National Council on Radiation Protection & Measurement (NCRP) identifies-

Answer 41

relative radiosensitivity of various tissues

Question 42

tissue weight factor (Wt)-

Answer 42

as WT increases, radio sensitivity of an organ increases

Question 43

NCRP pt effective dose-

Answer 43

not measured

Question 44

majority of occupational exposure is from-

Answer 44

fluoro

Question 45

rad. tech. occupational exposure effective dose recorded as-

Answer 45

appx. 10% of monitor dose

Question 46

rad. tech. effective dose used for-

Answer 46

radiation risk estimation

Question 47

rad. techs. role in radiologic terrorism-

Answer 47

-apply ALARA
-prevent stochastic effects

Question 48

radiologic devices (3)-

Answer 48

-rad. exposure device (RED)
-rad. dispersal device (RDD)
-improvise nuclear device (IND)

Question 49

rad. exposure device (RED)-

Answer 49

-sealed out source of radioactive material
-direct exposure
-doesn’t disperse
-no decontamination required

Question 50

rad. dispersal device (RDD)-

Answer 50

-explosive or non explosive
-disperses radioactive contamination over large areas
-troublesome, but not deadly

Question 51

examples of RDD-

Answer 51

powder in ventilation sys. or gas in water supply

Question 52

improvise nuclear device (IND)-

Answer 52

-material that can cause nuclear explosion
-unlikely to be used by terrorist
-if employed, damage would be extreme

Question 53

radiation protection guidance, protection should include (2 boundaries)-

Answer 53

inner & outer boundary

Question 54

inner boundary is established where readings are-

Answer 54

100 mGyA/hour

Question 55

outer boundary established at-

Answer 55

100 uGYA/hour

Question 56

radiation protection safety measures should include-

Answer 56

-detection
-alarm
-decontamination protocols
-prevention of recontamination

Question 57

Radiation protection safety measures will be dev. by-

Answer 57

hospitals RSO