Radiation Protection Stat Ch 8 9 RHB Rad

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 (1/16 TH pb) BARRIER: • PRIMARY RADIATION EXPOSURE – 99. 87% REDUCED • PORTABLE BARRIER = 99 % REDUCTION

PERSONNEL PROTECTION • • • PROTECTIVE APRONS – 0. 25 PB = 97% ↓ TO SCATTER 0. 5 PB = 99. 9% ↓ 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 / 5000 m. Rem • 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

• HIGH RADIAITON AREA – • 100 m. Rem ( 0. 1 rem / (1 ms. V) – @ 30 cm from the source of radiaton • RADIAITON AREA – • RHB: 5 m. Rem ( 0. 005 rem / (. 05 ms. V) – @ 30 cm from the source of radiation • PUBLIC 2 mrem per week* (STAT)

RHB “RULES” RHB RP PG 61 • 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 PG 62 • 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 m. Rem) • . 5 rem/ year. 05 rem/month • 5 m. Sv / 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