How far away must the operator stand from the xray tube if not covered with lead? - ACCURATE ANSWER-3 meters
90% of man made radiation to the population is related to? - ACCURATE 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+) - ACCURATE 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 required during interventional procedures - ACCURATE 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 must protective gloves/ gauntlets possess? - ACCURATE ANSWER-0.25mm of pb What lead equivalent must ceiling mounted lead screens and moveable shields provide? - ACCURATE ANSWER-0.50mm of pb
What are the annual radiation dose limits for radiation workers? - ACCURATE 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? - ACCURATE 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 - ACCURATE ANSWER-Primary barriers provide shielding from the direct xray beam. Such as, the walls and floor where the tube can be directed
-The wall behind the wall bucky
-Floor under the table
What are secondary barriers and give examples - ACCURATE 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 - ACCURATE ANSWER-Must not be less than:
-Mobile: 30cm
-Stationary: 38cm
-Radioscopic: 20cm (designed for special procedures that would be impossible at 30cm or 38cm)
What are the maximum air kerma rates for radioscopic equipment:
-with automatic intensity control
-without AIC - ACCURATE ANSWER-Not equipped with AIC: 50mGy/min
With AIC: 100mGy/min
The air kerma rate must not exceed ___ from scattered radiation of radioscopic equipment - ACCURATE ANSWER-2 mGy/h
HVL of Aluminum for given tube voltages? (70kV-150kV) - ACCURATE ANSWER-70: 2.5mm
80: 2.9mm
90: 3.2mm
100: 3.6mm