Stat Ch 8 & 9 RHB – Rad Prot Syllabus Radiation Protection Stat Ch 8 & 9 RHB – Rad Prot Syllabus

What is the difference between X-ray & Gamma?

RHB – Rad Prot – CH. IX p 51 ALARA (no minimum threshold) STOCHASTIC EFFECTS – NON TRESHOLD (CA + GENETIC) NON STHOCAHSTIC (DETERMINISTIC) SEVERITY OF EFFECTS VARIES WITH RADIATION DOSE (THRESHOLD) (CATARACTS, SKIN, BONE MARROW, STERILITY

PERSONNEL PROTECTION SCATTER FROM THE PATIENT TABLE TOP, COLLIMATOR, TUBE HOUSING, BUCKY STRAY RADIATION – LEAKAGE OR SCATTER RADIATION

PERSONNEL PROTECTION STANDING BEHIND A PROTECTIVE PRIMARY (1/16TH pb) BARRIER: PRIMARY RADIATION EXPOSURE – 99.87% REDUCED PORTABLE BARRIER = 99 % REDUCTION

PERSONNEL PROTECTION PROTECTIVE APRONS – 0.25 PB = 97% ↓ TO SCATTER THYROID SHEILDS (0.25 & 0.5) GLOVES (0.25 & 0.5)

PERSONNEL PROTECTION MONITORING FILM BADGE TLD POSL POCKET DOSIMETER RING BADGE

PERSONNEL PROTECTION MONITORING DOSE LIMITS WHOLE BODY EYES EXTREMITIES (BELOW ELBOW/KNEES)

Occupational Dose ANNUAL LIMITS WHOLE BODY = 5 REMS / 5000mRem LENS OF THE EYE = 15 REMS EXTREMITIES = 50 REMS

TLD

Ionization chamber

Report at least every quarter Preserved for a minimum of 3 years

RHB NOTIFICATION (EXP IN 24 HOURS) IMMEDIATE – WITHIN 24 HOURS TOTAL DOSE OF 25 rems Eye dose – 75 rem Extremity – 250 RADS OVEREXPOSURE – WITHIN 30 DAYS TOTAL DOSE OF 5 rems Eye dose – 15 rem Extremity - 50 REMS

LICENSE RENEWAL WITHIN 30 DAYS OF EXPRIATION NOTIFICATION OF CHANGE OF ADDRESS

PUBLIC 2 mrem per week* (STAT) HIGH RADIAITON AREA – 100 mRem ( 0.1 rem / (1 msV) @ 30 cm from the source of radiaton RADIAITON AREA – RHB: 5 mRem ( 0.005 rem / (.05 msV) @ 30 cm from the source of radiation PUBLIC 2 mrem per week* (STAT)

RHB “RULES” RHB RP PG61 LICENTIATES OF THE HEALING ARTS (MD, DO, DC, DPM) MUST HAVE A RADIOLOGY SUPERVISOR & OPERATORS PERMIT & CERTIFICATE TO OPERATE OR SUPERVISE THE USE OF X-RAYS ON HUMANS SUPEVISORS MUST POST THEIR LICENSES

RHB “RULES” RHB RP PG62 ALL XRAYS MUST BE ORDERED BY A PHYSICIAN VERBAL OR WRITTEN PRESCRIPTION See Section C – “Technologist Restrictions”

CARDINAL RULES TIME DISTANCE SHEILDING

SHEILDING PG 72 RHB HVL – expressed 2 ways HOW MUCH IT REDUCES THE ORGINAL BEAM INTENSITY HOW MUCH IS REQUIRED FOR BARRIER THICKNESS (amount needed to attenuated the beam

Room Sheilding Ch. 9 Workload Factor (W) -ma/sec/week – how much time during the week is the beam on Occupancy Factor (T) - # of people in room - beyond the barrier Use Factor (U) - % of time beam will strike a barrier (table pg 242) Primary vs Secondary Leakage Radiation

Which type of radiation is predominant above 80 kvp?

10 day rule No threshold for exposure Leukemia , congential abnormailies cander induction, resportion or death of the embryo and genetic effects Therapetuic Abortion “not justified” 25 rads or less – no injury seen ABSORBED DOSES – 50 RADS – could result in a spontaneous abortion

DOSE TO FETUS VS ESE

Pregnancy & Embryo Mother – occupational worker (5 rem) Baby – (500 mRem) .5 rem/ year .05 rem/month 5 mSv .5 mSv / month

Declared Pregnant Worker Must declare pregnancy – 2 badges provided 1 worn at collar (Mother’s exposure) 1 worn inside apron at waist level Under 5 rad – negligible risk Risk increases above 15 rad Recommend abortion (spontaneous) 25 rad (“Baby exposure” approx 1/1000 of ESE) www.ntc.gov/NRC/RG/08/08-013.html