Part 2 radiation protection

Question 1

What are the diagnostic x ray equipment’s ?

Answer 1

X ray tube housing , SLD , Collimator ( beam alignment) , Filtration , Exposure switch , QC ( exposure reproducibility

Question 2

What are the factors of room design and shielding ?

Answer 2

Primary beam direction , distance , occupancy factor , workload

Question 3

What is occupancy factor and workload ?

Answer 3

Uncontrolled area or controlled area ( barrier)

workload : is the treatment beam which directed at a given primary barrier
measured in milliampere min per week

Question 4

What are the detectors of radiation ?

Answer 4

Gas - filled : when ionized struck by radiation
applications : ion chambers , Geiger muller counters

Question 5

What is the purpose of personnel monitors ?

Answer 5

To measure the amount of radiation dose received
( required for the workers who exposed to radiation )

Question 6

What are the types of personnel monitors ?

Answer 6

Film badge , TLD , pocket dosimeter , OSL

Question 7

Components and principle’s of film badge ?

Answer 7

Plastic holder , Filters , Silver halide film

Principles : amount of density on film converted to amount / quantity of radiation
sensitive to 0.1 mSv

Question 8

Components and principle’s of TLD ?

Answer 8

Components :
Lithium fluoride crystal

Principles :
Crystal traps radiation energy
Heat releases light energy
environmental monitoring
Used for Whole body and extremity monitoring.
Sensitivity to light, especially UV and has 0.01 mSv

Question 9

Components and principle’s of pocket dosimeter ?

Answer 9

Components
Small ionization chamber
Self-reading electrometer

Principles
Radiation ionizes air in ionization chamber
Available in range of 0-200 mR

Question 10

Components and principle’s of OSL ?

Answer 10

Components
Aluminum oxide crystal

Principles :
Crystal traps radiation energy
Laser light releases light energy from crystal, which is the radiation exposure
Sensitive to 0.01 mSv (1 mrem)

Question 11

Occupational radiation dose

Answer 11

Is the radiation dose absorbed by workers during the work
Intended and unavoidable
Receive <1 mSv which determined by personnel monitoring device

Question 12

what are the 3 methods procedures of reducing radiation exposure ?

Answer 12

Reduce time spent
increase distance from the radiation source
wear shielding

Question 13

what is equivalent dose limit for fetus ?

Answer 13

5 mSv for entire pregnancy ( dose level)
Dose limit : 0.5 mSv

Question 14

what are the recommended dose limits ?

Answer 14

Effective dose and equivalent dose
20 mSv per year
averaged over defined periods of 5 years with no single year exceeding 50 mSv

Question 15

What are the effective dose limit of a worker and pregnant worker ?

Answer 15

Period : Average of 5 years effective dose : 100 mSv
During one year 50 mSv/year
Balance of pregnancy , 1 mSv / year

Question 16

what are the equivalent dose limits on a tissue ?

Answer 16

Lens of the eye 20 mSv/year , 100 mSv over 5 years , 50 mSv year in single year

Any point of the skin : 500 mSv / year
Extremities ( hands , feet) : 500 mSv /year

Question 17

Dose limits for public exposure in person and tissue ?

Answer 17

Member of the public ? one year / 1mSv / year

Lens of the eye : 15 mSv/ year
Any point of the skin : 50 mSv / year

Question 18

Dose constraint for industrial radiography and radio therapy ?

Answer 18

6 mSv year

Question 19

Dose constraint for diagnostic radiology ?

Answer 19

3 mSv year

Question 20

Hp (7) ?

Answer 20

Skin surface , Shallow dose

Question 21

Hp ( 10) ?

Answer 21

deep dose ( equivalent dose)
1 cm under the skin