Radiation Protection Viva Questions


1.      What is a dose

1.                  Abdorbed dose, units

2.                  What is air kerma

3.                  How does Air kerma and Absorbed dose in air vary (bremstrahlung)

4.                  What is Effective dose, Units

2.      What happens if a person received a whole body dose of 10Gy – what does this mean.

3.      What entrance dose do you expect from a chest exam, abdomenal exam. Any effects?

4.      What are deterministic effects?

5.      Do you see any deterministic effects in Diagnostic radiology?

6.      What is IRR99 mainly concerned with?

7.      What other regulations are concerned with radiation?

8.      What is IRMER concerned with – tell me what you know about IRMER?

9.      (expect them to mention referrer, practitioner, operator, written standard protocols for patient id, exposures, DRLs – expect them to know IRMER is about protecting the patients and ensuring the employer is responsible .

10. Local Rules – when are these required?

1.                  What must you have in Local Rules

2.                  What is a controlled area? – why do you have a controlled area?

11. Can you describe who and what are comforters and carers and give an example of when a person would be a comforter and carer? What differences are there under IRR 99 between comforter and carer and a member of the public? (1mSv dose limit dose not apply – 5mSv dose constraint is applied to C&Cs).

12. What dose limits are applied to staff, classified, non-classified?

13. Do you know what investigation levels are used and why?

14. What does a Geiger detect and why?

15. What is a compensated Geiger and what dose it detect?

16. Describe how a scintillation detector works and what it is used for.

17. Explain Stochastic and non-stochastic effects.

18. What is the best method for assessing dose to a patient? Effective dose

19. What is the range of effective doses in diagnostic radiology?

20. Where are you most likely to observe deterministic effects in radiology?

21. Have there been any reported cases in the UK?

22. What references would you use if you were designing an x-ray room?

23. What factors would you take into account?

24. How would you determine if the shielding in the room was adequate?

25. How would you assess patient doses?

26. What is a controlled area? Also wanted to know about local rules etc?

27. What are the requirements of a controlled area needs to be sign posted, staff etc?

28. For example in a nuclear medicine department what areas would be designated a controlled area?

29. What factors do you need to consider when you are handling radioisotopes? (distance, time, shielding).

30. What controls are there in place to protect the patient, IRMER?

31. Asked about TLD problems, and effect of kV and effective dose graphs: specific to portfolio.

32. Explain the different parts of an annual survey on a piece of fluoroscopy equipment.

33. Explain the set-up for dose rate measurements at the image intensifier face.

34. What dose rate would be measured typically?

35. What else do you have to take into consideration? (grid)

36. What would you do with the results of the survey and why? (compare them with baseline results to assess if there has been a change in performance)


37. What is effective dose and what is it measured in?

38. Why is it used in preference to just the dose to a particular organ/tissue?

39. For e.g. a chest X-ray, if you had the entrance dose how would you calculate the effective dose?

40. What is the minimum detectable dose of a TLD?

41. What would you expect your margin of error to be from a TLD?

42. How could you reduce the errors involved?

43. What else could you use to calculate effective dose?

44. Which is better and why?

45. What is dose-area-product?

46. Out of all diagnostic X-ray equipment, which would it be better to have a DAP meter installed into and why? i.e. according to the procedures carried out.

47. How would you convey the dose, or risk from a dose from a certain procedure to a member of public?

48. What is the received annual background dose?


49. When performing patient dose surveys for each room, what would you then check the doses against? (reference levels, other rooms)

50. If two rooms showed differing doses for the same type of exam, what would you check to try and explain this?


51. What changes in legislation will there be shortly?

52. What are the main points about this?

53. What are dose limits changing to/from?

54. What about extremities?

55. What are the main changes of IR(ME)R ’99, compared to IR(POPUMET)R ’88? (clinical/physical director => referrer, practitioner and operator)

56. Give examples of referrer, practitioner and operator?

57. Where do physicists come into this?

58. What about reference doses?