Radiation protection authorities exposure

The present distinction between radioactive waste that arises from operations of the nuclear fuel cycle and NARM waste provides an unnecessary impediment to development of a classification system that applies to all radioactive wastes. This distinction is not based on considerations of protection of public health but is based only on the source of the waste. NCRP notes that EPA s proposed guidance on radiation protection of the public (EPA, 1994d) encourages elimination of this legal distinction, because the guidance specifies that dose limits for all sources of radiation exposure combined and authorized limits for individual sources or practices should be applied to essentially all controllable sources, excluding indoor radon, not just to sources associated with the nuclear fuel cycle. 

Safety Objectives require that nuclear installations are designed and operated so as to keep all sources of radiation exposure under strict technical and administrative control. However, the Radiation Protection Objective does not preclude limited exposure of people or the release of legally authorized quantities of radioactive materials to the environment from installations in operational states. Such exposures and releases, however, must be stricdy controlled and must be in compliance with operational limits and radiation protection standards. 

A Radiation Protection Programme shall be established for the transport of radioactive material. The nature and extent of the measures to be employed in the programme shall be related to the magnitude and likelihood of radiation exposures. The programme shall incorporate the requirements of paras 301, 303-305 and 311. Programme documents shall be available, on request, for inspection by the relevant competent authority. 

Radiation exposures at the research reactor facility shall be subject to dose constraints that are set or approved by the regulatory body or another competent authority for the purpose of ensuring that the relevant dose limits are not exceeded. In all operational states, the main aims of radiation protection shall be to avoid unnecessary exposure to radiation and to keep doses below the dose constraints and as low as reasonably achievable, social and economic factors being taken into account. 

Radiation exposure to the public and the operating personnel shall be ensured in the design and operation to be as low as reasonably achievable (ALARA), social and economic factors being taken into account. This requirement implies that the hazardous consequences from the practice of radioactive waste incineration should be reduced by suitable protective measures to a value such that further reductions become less justified in relation to the additional expenditure required. The dose equivalent to individuals shall not exceed the applicable dose limits set by the competent authority. Further guidance on radiation protection principles may be found in Ref. [6]. 

National Committee on Radiation Protection (NCRP)—American committee of scientific authorities that published recommendations on maximum permissible exposure to radiation. 

Although during normal operation of research reactors exposure of the public due to the release of radioactive materials in the environment is expected to be negligible, a site-related assessment of such exposure should be performed prior to operation. The main objective of this assessment is to demonstrate compliance with the system of dose limitation as described in detail in IAEA Safety Series No. 9 "Basic Safety Standards for Radiation Protection 13). These evaluations are normally required by regulatory authorities and include estimating the effective dose equivalent for the most exposed members of the public (critical group) and collective effective dose equivalent commitment of the population ("collective dose"). 

Chinese hamsters exposed to ozone at 0.2 ppm for 5 h had an increased number of chromosomal breaks in their circulating lymphocytes. Blood samples for study were obtained immediately after exposure and 6 and 15.5 days later. The highest break frequency was observed after the longest delay. The authors compared the effects of X irradiation and ozone singly and combined, in their system. The combined effects were less than additive this suggested some protective mechanism, perhaps analogous to that observed by Hattori et al When the authors extrapolated their data to acceptable industrial-hygiene exposures to ozone and radiation, ozone was found to be much more likely than X irradiation to produce chromosomal breaks in such exposures. 

According to the rules laid down by the national nuclear regulatory authority (see, for example, Ret [11]), the consequences of a DBA should never result in any population exposure that would require countermeasures to protect people in the early period of the radiation accident. 

The purpose of this Safety Fundamentals publication is to define principles whose effective application will ensure appropriate protection and safety in any situation which involves or might involve exposure to radiation. It is intended to be used, as appropriate, by the Sponsoring Organizations in their international assistance operations and by national authorities and national organizations in their programmes. Moreover, it also provides a concise statement of the principles of protection and safety for decision makers in technical and policy matters. 

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