CAMRT EXAM QUESTIONS AND ACCURATE ANSWERS
How far away must the operator stand from the xray tube if not covered with lead? -
ANSWER 3 meters
90% of man made radiation to the population is related to? - ANSWER Medical
Radiography and Dental
For each peak xray voltage, what lead equivalent is required?
100kV or less (o-100)
Between 101kV-149kV
150kV or greater (150+) - ANSWER 0-100kV = 0.25mm of lead
Greater than 100kV but less then 150kV = 0.35mm of lead
150kV or greater = 0.50mm of lead
What protective equipment is worn when performing interventional procedures -
ANSWER Full wrap around protective gowns of 0.50mm pb in the front panels and
0.25mm pb in the back panels
Thyroid shields with an equivalent of 0.50mm of pb
Lead drapes/curtains mounted to II of 0.25mm of pb at 100kv
What lead equivalent do protective gloves/ gauntlets need to have? - ANSWER 0.25mm
of pb
,What lead equivalent must ceiling mounted lead screens and moveable shields provide?
- ANSWER 0.50mm of pb
What are the annual radiation dose limits for radiation workers? - ANSWER Whole body=
20mSv
Lens of eye= 150mSv
Skin = 500mSv
Hands = 150mSv
All other organs = 500mSv
For pregnant women an effective dose of 4 mSv must be applied for the remainder of the
pregnancy from all sources
What are the annual radiation dose limits to members of the public? - ANSWER Whole
body = 1mSv
Lens of the eye= 15mSv
Skin = 50mSv
Hands = 50mSv
All other organs = 50mSv
*these also apply for students*
What are primary protective barriers? Give examples - ANSWER Primary barriers
provide shielding from the direct xray beam. Such as, the walls and floor where the tube
can be directed
-Wall behind the wall bucky
-Floor under the table
, What are secondary barriers and give examples - ANSWER Provide shielding against
both leakage and scattered radiation. Walls that the primary beam is not directed
towards and the ceiling are secondary barriers.
The control booth is also a secondary barrier, the primary beam should never be
directed towards it.
What should the focal spot to skin distance be for:
-Mobile equipment
-Stationary equipment
-Radioscopic equipment - ANSWER Should not be smaller than:
-Mobile: 30cm
-Stationary: 38cm
-Radioscopic: 20cm (for special procedures which could not be performed at 30cm or
38cm)
What are the maximum air kerma rates for radioscopic equipment:
-with automatic intensity control
-without AIC - ANSWER Not fitted with AIC: 50mGy/min
With AIC: 100mGy/min
The air kerma rate must not exceed ___ from scattered radiation of radioscopic
equipment - ANSWER 2 mGy/h
How far away must the operator stand from the xray tube if not covered with lead? -
ANSWER 3 meters
90% of man made radiation to the population is related to? - ANSWER Medical
Radiography and Dental
For each peak xray voltage, what lead equivalent is required?
100kV or less (o-100)
Between 101kV-149kV
150kV or greater (150+) - ANSWER 0-100kV = 0.25mm of lead
Greater than 100kV but less then 150kV = 0.35mm of lead
150kV or greater = 0.50mm of lead
What protective equipment is worn when performing interventional procedures -
ANSWER Full wrap around protective gowns of 0.50mm pb in the front panels and
0.25mm pb in the back panels
Thyroid shields with an equivalent of 0.50mm of pb
Lead drapes/curtains mounted to II of 0.25mm of pb at 100kv
What lead equivalent do protective gloves/ gauntlets need to have? - ANSWER 0.25mm
of pb
,What lead equivalent must ceiling mounted lead screens and moveable shields provide?
- ANSWER 0.50mm of pb
What are the annual radiation dose limits for radiation workers? - ANSWER Whole body=
20mSv
Lens of eye= 150mSv
Skin = 500mSv
Hands = 150mSv
All other organs = 500mSv
For pregnant women an effective dose of 4 mSv must be applied for the remainder of the
pregnancy from all sources
What are the annual radiation dose limits to members of the public? - ANSWER Whole
body = 1mSv
Lens of the eye= 15mSv
Skin = 50mSv
Hands = 50mSv
All other organs = 50mSv
*these also apply for students*
What are primary protective barriers? Give examples - ANSWER Primary barriers
provide shielding from the direct xray beam. Such as, the walls and floor where the tube
can be directed
-Wall behind the wall bucky
-Floor under the table
, What are secondary barriers and give examples - ANSWER Provide shielding against
both leakage and scattered radiation. Walls that the primary beam is not directed
towards and the ceiling are secondary barriers.
The control booth is also a secondary barrier, the primary beam should never be
directed towards it.
What should the focal spot to skin distance be for:
-Mobile equipment
-Stationary equipment
-Radioscopic equipment - ANSWER Should not be smaller than:
-Mobile: 30cm
-Stationary: 38cm
-Radioscopic: 20cm (for special procedures which could not be performed at 30cm or
38cm)
What are the maximum air kerma rates for radioscopic equipment:
-with automatic intensity control
-without AIC - ANSWER Not fitted with AIC: 50mGy/min
With AIC: 100mGy/min
The air kerma rate must not exceed ___ from scattered radiation of radioscopic
equipment - ANSWER 2 mGy/h
