Radiation Saftey And Protection

Front 1

radiation measured in air

Back 1

exposure

Front 2

radiation with sufficient energy to separate an e- from its atom

Back 2

ionizing radiation

Front 3

alpha particles (6)

Back 3

-2 protons, 2 neutrons
-simply helium nuclei
-emitted from unstable heavy nuclei
-heavy mass
-can travel only short distances (most could be stopped with a sheet of paper)
-high LET

Front 4

Alpha particles

Back 4

charge= +2
at mass= 4
origin= nucleus

Front 5

Beta particles-
negatron
positron

Back 5

Negatron Positron
charge= -1 charge=+1
at mass= 0 at mass= 0
origin= nucleus origin= nucleus

Front 6

Neutrinos

Back 6

charge= 0
at mass= 0
origin= nucleus

Front 7

X-rays

Back 7

charge= 0
at mass= 0
origin= electron shells

Front 8

Gamma rays

Back 8

charge= 0
at mass= 0
origin= nucleus

Front 9

not stable and may exist for only very short periods of time

Back 9

positron

Front 10

when particles are emitted, they are accompanied by a ______.

Back 10

neutrino (small, massless, chargeless)

Front 11

The probability of bremstrahlung x-ray production is directly proportional to

Back 11

the square of the atomic number of the absorber

Front 12

The probability of bremstrahlung x-ray production is inversely proportional to

Back 12

the square of the mass of the incident particle

Front 13

___ radiation is much more likely to occur with ____ particles than with ____ particles

Back 13

beta particles then with alpha particles

Front 14

____ and ____ are both forms of electromagnetic radiation (photons)

Back 14

x-rays and gamma rays

Front 15

are extranuclear and result from rearrangements within the electron shells or from bremstrahlung radiation

Back 15

x-rays

Front 16

have no mass and no charge

Back 16

photons (x and gamma rays)

Front 17

___, ___, and ___ are the most common types of ionizing radiation used in radiaiton therapy

Back 17

x-rays, gamma rays, electrons

Front 18

__% of radiation exposure in US come from natural background sources

Back 18

82%

Front 19

originate from nuclear reactions in space or from our own sun

Back 19

cosmic rays

Front 20

the primary cosmic rays interact with molecules in the atmosphere to create other reactive agents known as

Back 20

secondary particles

Front 21

___, ___, and ___ may account for a variation of 10% in exposure

Back 21

latitude, solar cycles, and other factors

Front 22

exposure is higher at the ____ regions than at the equator

Back 22

polar regions

Front 23

the earth is made up of hundreds of materials, many of which are naturally radioactive

Back 23

terrestrial radiation

Front 24

terrestrial radiation consists of the presence of small amounts of _________

Back 24

long-lived isotopes of uranium, thorium, and radium ...

Front 25

The EPA estimates that ___ exposure is the 2nd leading cause of lung ca in the US, following smoking)

Back 25

radon exposure

Front 26

Internal exposure results from radioactive materials that are normally present in our bodies

Back 26

internal exposure

Front 27

examples of internal exposure

Back 27

-carbon -14
-hydrogen -3
-strontium -90
-potassium -40
-uranium
-thorium

Front 28

In ____the annual dose may be as great as __ mSv

Back 28

Kerala region of India
13 mSv (300 mrem)

Front 29

Exposure defined as the amount of ionization produced by photons in

Back 29

air per unit mass of air

Front 30

1 R=

Back 30

2.58X10^-4 C/kg

Front 31

is defined as the energy absorbed per unit mass of any material

Back 31

absorbed dose

Front 32

rad is ___ ergs of energy absorbed per gram

Back 32

100 ergs

Front 33

SI unit Gy is __ __ of energy absorbed per kilogram of absorbing material
1 Gy= __ cGy= __rad

Back 33

1Gy= 100 cGy = 100 rad

Front 34

takes into account the fact that different types of radiation produce different amounts of biologic damage

Back 34

dose equivalent

Front 35

alpha particles and neutrons are ___ -LET radiation and therefore have a ___ biologic effect than x-rays

Back 35

high-LET
greater

Front 36

QF
xrays and gamma rays

Back 36

1

Front 37

QF
Beta particles, positrons, and muons

Back 37

1

Front 38

QF
High-energy external protons

Back 38

1

Front 39

QF
Protons, other than recoil protons and energy >2 MeV

Back 39

2

Front 40

QF
Thermal neutrons

Back 40

5

Front 41

QF
Fast neutrons

Back 41

20

Front 42

QF
Alpha particles

Back 42

20

Front 43

QF
Fission fragments, other heavy nuclei

Back 43

20

Front 44

takes into account the effect of irradiation of only part of the body or the effect of nonuniform irradiation of the body

Back 44

effective dose equivalent

Front 45

the rate at which a radioactive isotope undergoes nuclear decay

Back 45

activity

Front 46

1 Ci= ___ mCi

Back 46

1000

Front 47

2 kinds of gas-filled detectors may be found in a radiation therapy department

Back 47

ionization chamber and Geiger-Muller

Front 48

consists of 2 electrodes within a gas-filled chamber, an applied voltage across the electrodes, and electronics and a meter to amplify and measure the electrical signal

Back 48

ionization chamber

Front 49

when ionization chambers are properly calibrated, their accuracy approaches __%

Back 49

2%

Front 50

a form of ionization used for personnel monitoring

Back 50

pocket dosimeter

Front 51

ionization chambers are __ __, they are not suitable for the detection of very low levels of radiation or radiation or radiation contamination

Back 51

not very sensitive

Front 52

because of their sensitivity, ___ ___ are best for finding contamination and other low levels of radiations

Back 52

G-M detectors

Front 53

because of their small size ___ are widely used to measure radiation

Back 53

thermoluminescent dosimeter (TLD's)

Front 54

The amount of blackness on film is called

Back 54

optical density

Front 55

optical density is related to the ___ ___ received by the film

Back 55

amount of radiation

Front 56

the relationship between density and film depend on ___, ___, and ___

Back 56

type of film, type and energy of the radiation, and the details of processing the film

Front 57

a typical __ __ has a slot with filters allow discrimination between different types of energies of radiation

Back 57

film badge

Front 58

__ __ radiation will not penetrate any of the filters but can reach the film in the area where no filters are present

Back 58

low-energy radiation

Front 59

cosmic

Back 59

8%

Front 60

terresterial

Back 60

8%

Front 61

internal

Back 61

11%

Front 62

medical x-rays

Back 62

11%

Front 63

nuclear medicine

Back 63

4%

Front 64

consumer products

Back 64

3%

Front 65

natural

Back 65

82%

Front 66

radon

Back 66

55%

Front 67

Activity is defined as

Back 67

rate of nuclear decay

Front 68

The source of ionizing radiation that contributes the most to exposure of the general population in the US

Back 68

natural background 82%

Front 69

Which type of device is best suited for output measurements of radiation therapy equipment

Back 69

ionization chamber

Front 70

Absorbed dose is defined as

Back 70

energy absorbed per unit mass

Front 71

Exposure is defined as

Back 71

ionization per unit mass of air by photons

Front 72

An alpha particle is best defined as

Back 72

short-range, relatively heavy-mass, high-LET particle