Transcript Radiation Protection Procedures

Radiation Protection
Procedures
Chapters 39-40 Bushong
Chapter 1 Sherer
Units of measurement
► Exposure
-Radiation intensity of air
 What is the unit of measurement?
► Dose-radiation
exposure
energy absorbed from radiation
 What is the unit of measurement?
► Effective
dose-biological effectiveness of the
radiation energy absorbed
 What is the unit of measurement?
► What
is the recommended dose limit for
radiologic personnel?




50 mSv/yr
5000mrem/yr
5rem/yr
All of the above
► The
occupational dose should not normallY
exceed 1 mSv/yr (100mrem/yr)
► See chart 40-1
► Fluoro/portables (Exposure =exposure rate
x time)
► Which is better for the operator in terms of
exposure in a fluoroscopy study
 Tube over patient?
 Tube under patient?
Personnel Exposure in
► Interventional
 What part of the body receives the highest dose?
► Mammography
 Requires minimal or no lead shielding. Why?
► CT
 Describe the beam in the CT room
► Surgery
 Interesting results from study
► Mobile
 Who must be “badged’?
Think of two reasons why society
is interested in exposure rates to
patients
ESE, GONADAL DOSE,MEAN
MARROW DOSE
► ESE
39-1 in Bushong or TABLE 1-5 (pg 20)
in Sherer.
► ESE and nomograms
► Mean marrow dose…see table 392(Bushong) and table 1-7 in Sherer…how
are they different?
Genetically Significant Dose
► Estimating
gonad dose = suspected genetic
effects of radiation
► Averages those patients who are irradiated
and those who are not
► Calculates the total genetic effect over a
large population
DOSE IN CT IMAGING
► SKIN
DOSE-HIGHER
► SPIRAL/MULTISLICE IMAGING –lower than
conventional CT Why?
► 10% OF X-RAYS ARE CT SCANS YET CT
SCAN ATTRIBUTE FOR 70% OF TOTAL
PATIENT EFFECTIVE DOSE
► CT dose= AVE FLUORO DOSE
► REDUCTION OF UNNECESSART PATIENT
DOSE- PGS 604-606
REDUCING OCCUPATIONAL
EXPOSURE
► 95%
of occupational exposure comes from?
► In fluoro, an RT should
► A portable the cord should be
► The three types of personnel monitors are?
► Describe how the radiation is calculated.
► MC RT students wear?
Sherer Chpt 1
► Diagnostic
Efficacy
► BERT Values
► Equivalent dose Eqd
► Effective dose EfD
REVIEW QUESTIONS IN
SHERER-PAGE 23-24