IAEA International Atomic Energy Agency Regulations Part III: Radiation Protection Performance Requirements Day 8 – Lecture 5(3)

IAEA 2 To provide an understanding of the basic concepts of justification, optimization and dose limitation. Objectives

IAEA 3 Justification of Practices Dose Limitation Optimization of Protection and Safety. Content

IAEA 4 General principles Benefit to the exposed individuals or the society shall offset the radiation harm, taking into account social, economic and other relevant factors. Justification of Practices Applicant for authorization provides sufficient evidence of the benefits versus harm. Justification is considered in the authorization process.

IAEA 5 Practical application Overall assessment of justification is made when new types of practices are proposed. Justification of Practices (cont) For individual cases, assessment is required that the practice is or will be conducted in a manner typical for existing types of practices that are already generally considered justified. The Regulatory Body should review the justification of existing types of practices whenever new important evidence on their efficacy or harm is acquired.

IAEA 6 Practices deemed unjustified include: the deliberate addition of radioactive substances in, or activation of:  food, feed, beverages, cosmetics (intake by, or application to, a human being);  toys, personal jewellery, adornments (frivolous use of radioactive substances);  human imaging using radiation used as a form of art or for publicity purposes; Justification of Practices (cont) any other practice determined by the Regulatory Body to be unjustified.

IAEA 7 Dose limits Occupational dose limits:  workers;  apprentices and students of years of age;  specially authorized exposures. Dose limits for the public Dose Limitation Dose limits are not applicable to medical exposures

IAEA 8 Workers Effective dose 20 millisieverts per year averaged over 5 years; 50 millisieverts in any single year. Dose Limits Equivalent dose to the lens of the eye; 20 millisieverts per year averaged over 5 years; extremities (hands and feet) and the skin; 500 millisieverts per year.

IAEA 9 Effective dose 6 millisieverts per year. Dose Limits (cont) Equivalent dose to the lens of the eye 20 millisieverts per year; extremities (hands and feet) and the skin: 150 millisieverts per year. Apprentices and students years of age

IAEA 10 Dose Limits (cont) Apprentices and students years of age (cont) No person under the age of 16 years shall be subjected to occupational exposure. No person under the age of 18 years shall be allowed to work in a controlled area unless supervised and then only for the purpose of training.

IAEA 11 Equivalent dose to the lens of the eye; 15 millisieverts per year. extremities (hands and feet) or the skin; 50 millisieverts per year. Dose Limits (cont) Members of the public Effective dose 1 millisievert per year. in special circumstances, a higher value of effective dose in a single year provided 1 millisievert per year over 5 years is not exceeded.

IAEA 12 Case by case approval of the Regulatory Body; Requirements: –radiation safety is optimized –workers involved have been consulted Specially authorized exposures Temporary change in some dose limit: –for a limited period of time –relates to specified work areas

IAEA 13 For exposures from any source within a practice the magnitude of individual doses, the number of people exposed, and the likelihood of incurring exposures; shall be kept as low as reasonably achievable (ALARA). Optimization of Protection and Safety

IAEA 14 Dose constraints are used in the context of optimisation within a practice; Optimization of Protection and Safety (cont) are established by the Regulatory Body; are less than dose limits; are not applicable to medical exposures; for public exposures, are a tool for considering contributions from different practices and sources.

IAEA 15 Reference Levels: represent the level of dose above which it is judged to be inappropriate to allow exposures to occur; Optimization of Protection and Safety (cont) used for optimization in emergency and existing exposure situations.

IAEA 16 Diagnostic reference levels; Dose constraints for exposures of carers and comforters and of volunteers program biomedical research; Criteria and guidelines for the release of patients under therapeutic procedures. Optimization of Protection and Safety (cont)