IAEA BSS WORKSHOP (2012): DOSE LIMITS & DOSE CONSTRAINTS

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1 REGIONAL WORKSHOP ON THE IAEA GENERAL SAFETY REQUIREMENTS: GSR PART 3 16 TO 20 APRIL 2012, KUALA LUMPUR IAEA BSS WORKSHOP (2012): DOSE LIMITS & DOSE CONSTRAINTS Hairul Nizam Idris Malaysia

2 Main Topic Introduction Dose Limit Dose Constraint Gaps in Existing Guidance and Needs for Improving Summary

3 INTRODUCTION The publication GSR Part 3 is a revision of the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (IAEA Safety Standards Series No. 115, Vienna, 1996) This presentation will cover aspect Dose Limits And Dose Constraints In Malaysia, aspect on Dose Limit & Dose Constrain are cover under Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations P.U. (A) 46 This regulation supersedes the previous regulation i.e. Radiation Protection (Basic Safety Standard) Regulations 1988

4 DOSE LIMITS

5 IAEA General Safety Requirements: GSR Part 3 - Schedule III (III-1: Dose limit for workers) Application Effective dose Lens of the eye Extremities or Skin Pregnant Female Worker/ Breast-feeding Dose Limit (msv) - 20 msv per year averaged over five consecutive years (100 msv in 5 years), and - 50 msv in any single year - 20 msv per year averaged over 5 consecutive years (100 msv in 5 years), and - 50 msv in any single year 500 msv in a year. - same broad level of protection as is required for members of the public 5

6 Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations Reg. 8: Dose limit for worker No. Dose Limit Dose Limit (msv) in a calendar year 1. Effective dose Note: With the condition the maximum effective dose averaged over a period of 5 consecutive years shall not exceed 20 msv Lens of the eye Skin Hands and feet Foetus Note: The foetus shall, from the date of the confirmation, shall not exceed 1 msv for the remaining period of the pregnancy 1 7

7 IAEA General Safety Requirements: GSR Part 3 - Schedule III (III-3: Dose limit for public exposure) Application Dose Limit (msv) Effective dose In special circumstances Lens of the eye Skin 1 msv in a year -a higher value of effective dose in a single year could apply, provided that the average effective dose over five consecutive years does not exceed 1 msv per year 15 msv in any single year 50 msv in a year. 8

8 Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations Reg. 9: Dose limit for members of the public No. Dose Limit Dose Limit (msv) in a calendar year 1. Member of Public 1 2. Lens of the eye Skin Knowingly assists in the support of patient Note: Shall not be allowed to continue when he received the effective dose exceeding the limit of 5 msv unless have given strong clinical justification 5. Person < 16 years visiting patient undergoing treatment and diagnostic examination involving RM 5 1 9

9 IAEA General Safety Requirements: GSR Part 3 - Schedule III (III-2: Dose limit for apprentices and students) apprentices between 16 and 18 years and students between 16 and 18 years Application Dose Limit (msv) Effective dose - 6 msv in a year Lens of the eye Extremities or Skin - 20 msv in a year 150 msv in a year. 10

10 Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations Reg. 10: Dose limit for apprentices and students (apprentices between 16 and 18 years and students between 16 and 18 years) No. Dose Limit Dose Limit (msv) in a calendar year 1. Effective dose 6 2. Equivalent dose - lens of the eye Equivalent dose - hands and feet Equivalent dose - skin

11 DOSE CONSTRAINS

12 IAEA General Safety Requirements: GSR Part 3 - Dose constraints and Reference levels Dose constraints Dose constraints are applied to occupational exposure and to public exposure in planned exposure situations. Dose constraints are set separately for each source under control and they serve as boundary conditions in defining the range of options for the purposes of optimization. Dose constraints are not dose limits; exceeding a dose constraint does not represent non-compliance with regulatory requirements, but it could result in follow-up actions.

13 Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations Reg. 7: Dose constraint (DS) Dose Constraint a prospective restriction on dose, primarily intended to be used to discard undesirable options in an optimization calculation. Every licensee shall ensure that, except for medical exposure, the optimization of the protection and safety, shall- Not exceed the DS or values which can the dose limits (DL) to be exceeded ;and ensure that for any radiation source and radwaste management facility that can release radioactive material into the environment, the cumulative effects of each annual release from the radiation source are restricted so that the effective dose in any year to any member of the public, including people distant from the radiation source and people of future generations, is unlikely to exceed any relevant dose limit, taking into account the cumulative releases and the exposures expected to be delivered by all other relevant radiation sources and practices

14 GAPS IN EXISTING GUIDANCE and NEEDS FOR IMPROVING Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations 2010 o all dose limits (DL) and value are base on BSS 115 (1996) and ICRP 103 o Dose limit on the effective dose for a worker fix to 20mSv in a calendar year (in GSR Part 3 50mSv in any single year) o Dose limit value for lens of the eye base on BSS 115 (1996) o Not mentioned about DL for female workers who are breast-feeding o not mentioned about existing exposure situation o no statement / explanation about Reference Level

15 SUMMARY Malaysia s Atomic Energy Licensing (Basic Safety Radiation Protection) Regulations 2010 is released on 2010 and it developed base on old IAEA BSS 115 (1996) & ICRP 103 So there is some gap with the IAEA revised BSS (2011) Malaysia government or regulatory body is unlikely to revise the regulation in the immediate future. Advice & recommendation from IAEA is needed to full fill the gaps

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