Radiation protection systems

Section 1 of the Report presents the quantities Hz and E and the relationship of each quantity to its corresponding radiation protection system. Section 2 describes the use of personal monitors for workers in the United States, including their calibration and how they are worn on individuals in various occupational settings. Section 3 discusses practical ways to use one or two personal monitors to obtain estimates of Hz and E. Section 4 provides the NCRP s... 

Contemporary radiation protection systems (ICRP, 1977a 1991 NCRP, 1987 1993) include dose limits expressed in such a quantity. To obtain the quantity, absorbed doses are first multiplied by a quality factor (ICRP, 1977a) or a radiation weighting factor (ICRP, 1991), selected for the type and energy of the radiation incident upon the body, yielding, respectively, the dose equivalent in the tissue (ICRP, 1977a) or equivalent dose in the tissue (ICRP, 1991). Therefore ... 

Also, a dose limit expressed in the quantity He does not carry the same implications for radiation protection as a numerically equal dose limit expressed in the quantity E. For example, a value of He = 10 mSv and a value of = 10 mSv do not carry the same implications for radiation detriment in a working population, as noted in Sections 1.2,2 and 1.2,3. One must be consistent in using He or E only in the context of its corresponding radiation protection system [i.e., He with the ICRP (1977a) or the NRC (1991) systems E with the ICRP (1991) or the NCRP (1993) systems]. 

SC 88 Fluence as the Basis for a Radiation Protection System for Astronauts... 

Schlenker RA. 1986. Comparison of intake and committed dose equivalent permitted by radiation protection systems based on annual dose equivalent and committed dose equivalent for a nuclide of intermediate effective half-life. Health Phys 51 207-213. 

The position of the radionuclide in the molecule of interest is also critical as it will affect the biological behavior of the radiopharmaceutical. Chemical reactions must be designed to be stereospecific in many cases, as the production of a mixture of different stereoisomers complicates the purification of the final radiopharmaceutical. Synthesis procedures must also be easy to automate, as very elevated activities are used for the synthesis of PET radiopharmaceuticals (several curies usually) and appropriate radiation protection systems must be used. 

Type 2 isolators for use with radiopharmaceuticals should incorporate an appropriate radiation protective system against ionising radiations. 

The scheme of coolant moving within the MCC is as follows throu die windows of reactor outlet chamber the coolant heated in the core flows to the inlet of the SG twelve modules which have parallel connection. It flows from top to bottom in the intertube gap of the SG modules and is cooled there. Then the coolant penetrates into the intermediate chamber, from which it moves in the channels of in-vessel radiation protection system, cooling it, to the monoblock upper part and there it forms the free level of cold coolant (peripheral buffer chamber), further from Ae monoblock upper part the coolant flow moves to the MCP suction inlet. 

Radiation protection systems shall be provided for research reactors to ensure adequate monitoring for radiation protection purposes in operational states, DBAs and, as practicable, BDBAs, including ... 

Larger microprocessor systems, with programs requiring several tens of kilobytes of memory, are used in the radiation protection system. 

Since 1982, microprocessor systems have also been or are being qualified for use in nuclear applications, starting with applications in the radiation protection system. The problems that have arisen with computer systems have not been more serious than the problems that otherwise would be regarded as... 

The IAEA has issued several publications that provide practice specific information regarding the use of radiation sources in a safe and secure manner [19,20,24-32]. These publications should be consulted when preparing a safety assessment or establishing a radiation protection system. Other IAEA publications provide practice specific checklists with items to be considered in the authorization of applications and in the performance of inspections by the regulatory body [33,34]. 

Administrative controls form part of the radiation protection system for a facility. Examples of factors relevant to establishing a radiation safety system for an industrial irradiation facility are given in Annex 1. 

The radiation protection system of PARR-1 consists of 9 radiological channels measuring radiation levels in different active areas in and around the reactor building. Most of these channels were interfaced with the PC. Other nuclear and process chaimels which could be connected with the computer are ... 

Although the presented results prove the efficiency of radioscopy, this system have certain characteristics which justify to develop and employ further process integrated testing systems. One of this characteristics is that the integration of radioscopy in industrial applications is doubtful because of reasons of radiation protection. This means, that the results from radioscopy should rather be used to fit other systems (acoustic emission analysis or temperature analysis) for industrial applications. 

Anti-inflammatory [62BRP897870, 62BRP898414 73GEP(O)2261095 74USP3850932 77USP4053600), antitumor (92KFZ30), and radiation-protective (92KFZ30) properties were documented for some compounds of this system. 

In International Radiation Protection Society. Radiation protection A systemic approach to safety Proceedings of the 5th congress of the International Radiation Protection Society, Jerusalem, March 1980. New York Pergamon Press, 607-610. 

Where facilities are exposed to the constant radiation of the sun, sun shades are provided over exterior exposed equipment that may not function properly at elevated temperatures or would deteriorate rapidly if left continual exposed to the direct sunlight. Most electrical or electronic equipment is rated for a maximum operating temperature of 40 °C (104 °F) unless otherwise specified, e.g., hazardous area lighting temperatures are normally specified for 40 °C (104 °F) limit. Of particular concern for fire protection systems are those containing storage for foam concentrates rubber hoses or other rubber components which may dry and crack. 

All these radical cations are fairly strong oxidants. For example, the monomeric methionine radical cation is likely to propagate oxidative damage in peptides (Rauk et al. 2000). Yet in cellular systems, thiourea has radiation-protective properties (Bacq 1965). This may be accounted for considering that the oxidative power of its dimeric radical is not high enough to oxidize even G it reacts only reasonably fast when G is deprotonated (Schuchmann et al. 2000), and this is a non-relevant situation in DNA. 

Skin constitutes the interface between the human body and the environment. It represents a major target of oxidative stress since it is exposed to external oxidant aggressions like UV radiation, ozone, chemicals or pollution. Continuous exposure to such damaging effects and/or deficiency of the antioxidant protection systems result in skin premature aging and contribute to the development of cutaneous diseases and cancers [23]. Electrochemical studies dealing with the effect... 

This Report presents recommendations of the National Council on Radiation Protection and Measurements (NCRP) on a new system for classifying waste that contains hazardous substances, either radionuclides or hazardous chemicals. NCRP s recommendations incorporate three principles. 

Exempt Radioactive Wastes. The radioactive waste classification system in the United States does not include a general class of exempt waste (see Table 1.1). Rather, many products and materials that contain small amounts of radionuclides (e.g., specified consumer products, liquid scintillation counters containing 3H and 14C) have been exempted from requirements for use or disposal as radioactive material on a case-by-case basis. The various exemption levels are intended to correspond to low doses to the public, especially compared with dose limits in radiation protection standards for the public or doses due to natural background radiation. However, the exemption levels are not based on a particular dose, and potential doses to the public resulting from use or disposal of the exempt products and materials vary widely. 

Similar considerations apply to the discussions of approaches to risk management in Section 3.3. Readers who are knowledgeable about principles of radiation protection may not be familiar with the different approach to health protection used for hazardous chemicals, and vice versa, and an understanding and resolution of the different approaches to risk management is important in developing a comprehensive and risk-based waste classification system. 

Established Exemption Levels. NRC s radiation protection standards in 10 CFR Part 20 (NRC, 1991) include limits on concentrations or annual releases of radionuclides for unrestricted discharge into sanitary sewer systems, except any excreta from individuals undergoing medical treatment with radioactive material are exempt from the limits. These regulations also include an exemption for land disposal of liquid scintillation materials and animal carcasses that contain 2 kBq g 1 (0.05 pCi g-1) or less of 3H or 14C, although the exempted scintillation materials must be managed in accordance with RCRA requirements due to the presence of toluene. 

This Section briefly reviews previous recommendations of NCRP that are potentially relevant to the development of a risk-based waste classification system. The topics discussed include NCRP s recommendations on radiation protection of the public and the comparative hazards of ionizing radiation and chemicals. 

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. 

DORNSIFE, W.P. (1995). Practical applications of a risk-based waste classification system, pages 113 to 145 in Radioactive and Mixed Waste—Risk as a Basis for Waste Classification, NCRP Symposium Proceedings No. 2 (National Council on Radiation Protection and Measurements, Bethesda, Maryland). 

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