Radiation Protection Radiation Protection ProceduresProcedures

Chapters 39-40 BushongChapters 39-40 Bushong

Chapter 1 Sherer Chapter 1 Sherer

Units of measurementUnits of measurement

► Exposure -Radiation intensity of airExposure -Radiation intensity of air What is the unit of measurement?What is the unit of measurement?

►Dose-radiation energy absorbed from Dose-radiation energy absorbed from radiation exposureradiation exposure What is the unit of measurement?What is the unit of measurement?

► Effective dose-biological effectiveness of the Effective dose-biological effectiveness of the radiation energy absorbed radiation energy absorbed What is the unit of measurement?What is the unit of measurement?

►What is the recommended dose limit What is the recommended dose limit for radiologic personnel?for radiologic personnel? 50 mSv/yr50 mSv/yr 5000mrem/yr5000mrem/yr 5rem/yr5rem/yr All of the above All of the above

►The occupational dose should not The occupational dose should not normallY exceed 1 mSv/yr (100mrem/yr)normallY exceed 1 mSv/yr (100mrem/yr)

►See chart 40-1See chart 40-1►Fluoro/portables (Exposure =exposure Fluoro/portables (Exposure =exposure

rate x time)rate x time)►Which is better for the operator in terms Which is better for the operator in terms

of exposure in a fluoroscopy studyof exposure in a fluoroscopy study Tube over patient?Tube over patient? Tube under patient?Tube under patient?

Personnel Exposure inPersonnel Exposure in

► InterventionalInterventional What part of the body receives the highest dose?What part of the body receives the highest dose?

►MammographyMammography Requires minimal or no lead shielding. Why? Requires minimal or no lead shielding. Why?

► CTCT Describe the beam in the CT roomDescribe the beam in the CT room

► SurgerySurgery Interesting results from studyInteresting results from study

►MobileMobile Who must be “badged’?Who must be “badged’?

Think of two reasons why Think of two reasons why society is interested in society is interested in

exposure rates to patients exposure rates to patients

ESE, GONADAL DOSE,MEAN ESE, GONADAL DOSE,MEAN MARROW DOSEMARROW DOSE

►ESE Table 39-1 in Bushong or TABLE ESE Table 39-1 in Bushong or TABLE 1-5 in Sherer.1-5 in Sherer.

►ESE and nomogramsESE and nomograms►Mean marrow dose…see table 39-Mean marrow dose…see table 39-

2(Bushong) and table 1-7 in Sherer…2(Bushong) and table 1-7 in Sherer…how are they different? how are they different?

Genetically Significant DoseGenetically Significant Dose

►Estimating gonad dose = suspected Estimating gonad dose = suspected genetic effects of radiationgenetic effects of radiation

►Averages those patients who are Averages those patients who are irradiated and those who are notirradiated and those who are not

►Calculates the total genetic effect over Calculates the total genetic effect over a large populationa large population

DOSE IN CT IMAGINGDOSE IN CT IMAGING

►SKIN DOSE-HIGHERSKIN DOSE-HIGHER►SPIRAL/MULTISLICE IMAGING –lower than SPIRAL/MULTISLICE IMAGING –lower than

conventional CT Why?conventional CT Why?►10% OF X-RAYS ARE CT SCANS YET CT 10% OF X-RAYS ARE CT SCANS YET CT

SCAN ATTRIBUTE FOR 70% OF TOTAL SCAN ATTRIBUTE FOR 70% OF TOTAL PATIENT EFFECTIVE DOSEPATIENT EFFECTIVE DOSE

►CT dose= AVE FLUORO DOSECT dose= AVE FLUORO DOSE►REDUCTION OF UNNECESSART PATIENT REDUCTION OF UNNECESSART PATIENT

DOSE- PGS 604-606DOSE- PGS 604-606

REDUCING OCCUPATIONAL REDUCING OCCUPATIONAL EXPOSUREEXPOSURE

►95% of occupational exposure comes 95% of occupational exposure comes from?from?

► In fluoro, an RT shouldIn fluoro, an RT should►A portable the cord should beA portable the cord should be►The three types of personnel monitors The three types of personnel monitors

are?are?►Describe how the radiation is calculated. Describe how the radiation is calculated. ►MC RT students wear? MC RT students wear?

SHERER CHAPTER 1 SHERER CHAPTER 1 RADIATION PROTECTIONRADIATION PROTECTION

►Diagnostic EfficacyDiagnostic Efficacy►TDSTDS►ALARAALARA►ORPORP►BERT ValuesBERT Values►Equivalent dose EqdEquivalent dose Eqd►Effective dose EfDEffective dose EfD

Sherer Chpt 1Sherer Chpt 1Manmade RadiationManmade Radiation

►Products EqDProducts EqD►Air Travel EqDAir Travel EqD►Nuclear fuel EqDNuclear fuel EqD►Fallout from Nuclear testing EqDFallout from Nuclear testing EqD►Nuclear AccidentsNuclear Accidents

Three mile islandThree mile island ChernobylChernobyl

►The Ethos projectThe Ethos project►Medical RadiationMedical Radiation

REVIEW QUESTIONS REVIEW QUESTIONS IN SHERER-PAGE 23-IN SHERER-PAGE 23-

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