Radiation Monitoring

Question 1

Worker who occasionally works in a controlled area and may receive significant occupational exposure needs to be

Answer 1

Monitored indivudually

Question 2

Personnel Monitoring Devices

Answer 2

FPOT

Film badge dosimeter
Pocket dosimeter
Optically stimulated luminescence
Thermoluminescent dosimeter

Question 3

Purpose of personnel monitoring devices are

Answer 3

ICA

Identifies high dose
Control of radiation exposure
Assessment if working places

Question 4

Commonly used to measure and record radiation exposure sue to gamma rays, X-rays and beta particles

Answer 4

Film badge dosimeter

Question 5

The film in film badge dosimeter

Answer 5

Packed in a light proof, vapor proof envelope preventing light, moisture or chemical vapors from affecting the film

Question 6

Film is coated with

Answer 6

Two emulsion

Question 7

Emulsions in FBD

Answer 7

1. Large grain, fast emulsion that is sensitive to low levels of exposure
2. Fine grain, slow emulsion that is less sensitive to exposure

Question 8

Causes of inaccuracy of FBD

Answer 8

EDEH

Effect of dosage on the film but not received by the wearer
Effect of hear on film

Question 9

Advantages of FBD

Answer 9

ACAP

Accurate for exposures greater than 100mrem
Can measure doses due to different types of radiation
Able to distinguish diff energies of photons
Provides permanent record

Question 10

Worn between the neck and the waist

Answer 10

Whole body badges

Question 11

Worn on a finger of the hand most likely to be exposed too ionizing radiation

Answer 11

Ring badges

Question 12

It is worn for a period of tine (3 months pr less)

Answer 12

Thermoluminescence Dosimeter (TLD)

Question 13

TLD is a phosphor such as

Answer 13

Lithium Fluoride

calcium Fluoride

Question 14

TLD’s can measure doses as low as

Answer 14

1 mrem

Question 15

Advantages of TLD

Answer 15

RRLS

Reusable
Relative energy independence
Linearity of response to dose
Sensitive to low doses

Question 16

Disadvantage of TLD

Answer 16

No permanent record

Question 17

It means emitting light when heated

Answer 17

Thermoluminiscent

Question 18

It is a process in which a pre-irradiated material when subjected to an appropriate optical stimulation, emits light signal proportional to the absorbed dose

Answer 18

Optically Stimulated Luminescence

Question 19

Stimulation is carried out

Answer 19

Optically rather than thermally

Question 20

OSL emission is highly influenced by

Answer 20

Energy

Intensity of the stimulating optical beam

Question 21

It is the simplest and the most straight forward OSL process in which a pre-irradiated material is stimulated by a light source of constant intensity

Answer 21

Continuous wave optically stimulated luminescence

Question 22

A process in which the optically stimulated luminescence signal from a pre-irradiated material is measured after a stimulation light is switched off

Answer 22

Delayed optically stimulated luminescence

Question 23

A form of DOSL in which the luminescence is recorded intermittently following a stimulation by very short pulses with a frequency of about thousands of hertz

Answer 23

Pulsed optically stimulated luminescence

Question 24

These are used to provide the wearer with an immediate reading of his or her exposure to x-rays and gamma rays

Answer 24

Pocket dosimeter

Question 25

They are commonly worn in the pocket

Answer 25

Pocket dosimeter

Question 26

Two types of pocket dosimeter

Answer 26

DD Direct read pocket dosimeter Digital electronic doaimeter

Question 27

The dosimeter contains a small ionization chamber with a volume of approximately two millemeters

Answer 27

Direct read pocket dosimeter

Question 28

The electrons produced by ionization are attracted to, and collected by

Answer 28

Positively charged central anode

Question 29

The amount of movement is ________________ to the amount of ionization which occurs

Answer 29

Directly proportional

Question 30

It is viewed on a translucent scale which is graduated in units of exposure

Answer 30

Fiber

Question 31

Advantages of DRPD

Answer 31

Immediate reading | Reusable

Question 32

Disadvantages of DRPD

Answer 32

Limited range Inability to provide a permanent record Reading loss due to dropping

Question 33

These dosimeters record dose information and dose rate

Answer 33

Digital electronic dosimeter

Question 34

DED most often use

Answer 34

Geiger Müller counters

Question 35

Digital electronic dosimeter includes what feature which emits an audible signal or chirp with each recorded increment of exposure

Answer 35

Audible alarm

Question 36

Types of workplace/ area monitoring

Answer 36

PIGS Proportional counters Ionization chambers GM tubes Scintillation detectors

Question 37

The choice of monitoring instrument depends on

Answer 37

PHER Photons or particles High or low levels Energy of photons Required accuracy

Question 38

Contamination detectors for Beta emitters

Answer 38

GM tube | Proportional counter

Question 39

It is the simplest of all gas-filled radiation detectors, and is widely used for the detection and measurement of certain types of ionizing radiation, x-rays and gamma rays and beta particles

Answer 39

Ionization Chamber

Question 40

The essential component of ionization chamber are the

Answer 40

Anode and cathode

Question 41

The potential difference between the anode and cathode

Answer 41

100-500 volt range

Question 42

The most commonly used for quantifying alpha and beta activity, they are also used for neutron detection

Answer 42

Proportional counters

Question 43

The pulses produced by a proportional counter are larger that those produced by

Answer 43

Ionization chamber

Question 44

In proportional counters it usually serves as the cathode

Answer 44

Cylinder

Question 45

In a proportional counters the anode is made up of

Answer 45

Fine metal wire stretched along the axis of the cylinder

Question 46

It occurs near the anode at a distance comparable to the wire's diameter

Answer 46

Gas amolification

Question 47

Proportional counter are filled with

Answer 47

Inert gas

Question 48

It is an instrument used for measuring ionizing radiation such as alpha particles, beta particles and gamma rays using ionization effect produced in a Geiger-Müller tube

Answer 48

Geiger counter

Question 49

Used to detect presence of low-level radioactive particles and rays

Answer 49

Geiger counter

Question 50

The Gm tube is filled with an inert gas such as

Answer 50

Helium Argon Neon

Question 51

The most important resource a radiographer has

Answer 51

Survey meters

Question 52

To determine

Answer 52

The presence and intensity of radiation

Question 53

Are portable radiation detection and measurement instruments used to check personnel, equipment and facilities for radioactive contaminatin

Answer 53

Survey meters

Question 54

To measure external or ambient ionizing fields

Answer 54

Survey meters

Question 55

One of the oldest type of radiation detector bc measurements could be made with photographic film

Answer 55

Scintillation detectors

Question 56

A material that exhibits scintillation when exposed bu ionizing radiation

Answer 56

Scintillator

Question 57

Types of inorganic scintillators

Answer 57

Cesium iodide with thalium Cesium iodide with sodium Sodium iodide with thanlium

Question 58

The most common type of material is a type of salt called

Answer 58

Sodium-iodide

Question 59

The light produced from the scintillation process is reflected through a clear window where it interacts with device called

Answer 59

Photomultiplier tube

Question 60

To minimize contamination risks

Answer 60

Use protective gloves and clothing Adopt clean operating conditions Adopt good laboratory practice

Question 61

Types of monitoring

Answer 61

PA Personnel monitoring Area/Workplace monitoring