Week 2 :Radiation Protection

1. Week 2 :Radiation Protection RTEC 111 Bushong Ch 1 & 38

2. Do I have your attention?

5. Why are x-rays harmful?

8. Reduction of Occupational Radiation Exposure • Radiography as a profession is very safe .. if you follow the ALARA rules • Most technologist exposure occurs from fluoroscopy exams and mobile exams • During all fluoroscopy and mobile exams technologists should wear a protective apron • The primary beam should never be pointed at the tech or other staff… primary at the patient!

9. ALARA • ALWAYS KEEP RADIATION EXPOSURES AS LOW AS REASONABLY ACHIEVABLE • Can you think of ways to do this?

10. CARDINAL RULESOF RADIATION PROTECTION • Time • Distance • Shielding

12. TIME • The exposure is to be kept as short as possible because the exposure is directly proportional to time. • 20 mrem = 2min • 10 mrem = 1min

13. DISTANCE • Distance from the radiation source should be kept as great as possible • Physical Law: • Inverse Square Law

14. INTENSITY IS SPREAD OUT…

15. Position • When primary beam is on.. Your distance should be kept as great as possible • The dead man foot or hand switch should be used sparingly • The closer you are to the patient or primary beam the more exposure you are receiving.

16. Holding patients • ECC policy: • STUDENT RADIOGRAPHERS ARE NOT PERMITED TO HOLD PATIENTS FOR PROPER POSITIONING DURING EXPOSURES • Mechanical devices should be used

17. Immobilization

18. Holding patients • Otherwise, a relative or friend accompanying the patient should be asked to help • Occasionally, other hospital employees such as nurses and orderlies may be asked to help • Radiology staff should never hold patients

19. If holding a patient is required… • Use shielding • Apron, gloves, thyroid shield, glasses • Avoid exposing assisting person to the primary beam.

20. SHIELDING • A lead protective shield is placed between the x-ray tube and the individuals exposed, absorbing unnecessary radiation

22. Primary Barriers

23. SHIELDING TECHNOLOGIST . 25 mm LEAD • LEAD APRON, GLOVES • THYROID SHIELD, GLASSES PATIENT – GONAD SHEILDING . 5 mm LEAD

24. GONAD SHIELDING • MUST BE . 5 MM OF LEAD • MUST BE USED WHEN GONADS WILL LIE WITHING 5 CM OF THE COLLIMATED AREA (RHB) • KUB. Lumbar Spine Pelvis • male vs female shielding

25. TYPES OF SHIELDING • Flat or contact • Shaped • Shadow

26. Flat/Contact

28. Shadow Shield

30. Your first exam! 2V CXR • A wrap-around apron would be better • Why?

31. Minimizing radiation exposure • Is easy the equipment is designed to !! • Filtration • Intensifying screens • Protective barriers • Mechanical restraining devices

32. Filtration REDUCES PATIENT EXPOSURES • REMOVES LOW ENERGY PHOTONS

33. Minimizing radiation exposure • Is easy when technologist and student technologist are informed! • Collimation • Protective apparel/Gonadal shielding

35. Permissible Occupational Dose • Annual dose: • 5 rem / year 50 mSv / year • Cumulative Dose • 1rem x age 10mSv X age

36. Occupational DoseANNUAL LIMITS • WHOLE BODY = 5 rem / 5000 mRem • LENS OF THE EYE = 15 rem • EXTREMITIES = 50 rem

37. OCCUPATIONAL EXPOSURES • 5 rem / YEAR BUT NOT TO EXCEED 1.25 rem/QUARTER • OLD “MPD 5(Age – 18)”

38. PUBLIC EXPOSURE • 10 % OF OCCUPATIONAL • (MUST BE MONITORED IF ABOVE 10%) • NON MEDICAL EXPOSURE • .1 rem OR 100 mrem OR 1 mSv (Freq) • .5 rem OR 500 mrem OR 5 mSv (Infreq) • UNDER AGE 18 & STUDENTS • .1 rem OR 1 mSv

39. Personnel Monitoring Devices • Film Badges • TLD / OSL • Pocket Dosimeter • Ring Badge

41. Occupational radiation monitor does NOT protect against radiation exposure!

42. Occupational radiation monitor • Should be a life time dose record • Should NOT be worn when YOU are the patient • Should be left at the hospital for safe keeping • Should be stored in a radiation free area

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

45. 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

46. Fetal Exposure • (“Baby exposure” approx 1/1000 of ESE) • ALWAYS ASK LMP before exposure made … any females that could be exposed to primary or scatter

47. Reduction of unnecessary patient dose • Unnecessary exam • If the order is unclear…clarify • If the order is wrong.. Fix it • Repeat exams

48. Patient Positioning • When ever possible primary exposure to the gonads, breasts, lenses of the eyes and thyroid should be avoided. • Especially female patients… perform exams PA as apposed to AP • PA = posterior anterior • AP = anterior posterior

49. I don’t think so…..

50. That’s all folks….Questions?