Protection of Personnel Week 2 Flashcards
(21 cards)
What is the xray tube enclosed in?
lead-lined metal covering requiring 1/16 inch lead
Leakage radiation from the xray tube housing should not exceed what parameters?
100mR/hr within a distance of 1 meter from the tube
Factors that help determine required barrier thickness
Occupancy, workload, and use
Radiation survey instruments
Geiger-Muller and cutie pie meter
Area occupied by radiology personnel and patients
Controlled Area
Radiation in the Controlled area cannot exceed
100 mRem/week
Area occupied by the general public
Uncontrolled area
Radiation in the uncontrolled area cannot exceed
1mgy/yr
Barrier perpendicular to the xray beam and are designed to withstand the strength of a full primary radiation
Primary Barrier
Requirements of Primary Barriers
1/16 inch lead, 7 ft tall
Minimum requirement for filtration on x-ray equipment operating above 70 kVp
2.5 mm AL
Barriers around the room designed to absorb scatter radiation
Secondary barriers
Requirement of secondary barriers
1/32 inch lead
Thickness of material required to reduce the intensity of a xray or gamma ray beam to one half of its initial value
Half Value Layer (HVL)
Thickness of lead apron
0.25 mm lead
Thickness of lead gloves
0.25 mm lead
Thickness of thyroid shield
0.5 mm lead
Thickness of lead glasses
0.35 mm lead
The intensity of radiation at a given distance from a point source is inversely proportional to the square of the distance of the object from the source
Inverse Square Law
If we double the distance from the source, what happens to the intensity?
Intensity of new distance is 1/4 as much as the original intensity
How to adjust for involuntary motion of patients
Use a high mA and short exposure time
