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===[[ICRP Publication 103]] paragraph 27===
<blockquote>... The Recommendations are based on scientific knowledge and on expert judgement. Scientific data, such as those concerning health risks attributable to radiation exposure, are a necessary prerequisite, but societal and economic aspects of protection have also to be considered. All of those concerned with radiological protection have to make value judgements about the relative importance of different kinds of risk and about the balancing of risks and benefits. In this, radiological protection is not different from other fields concerned with the control of hazards ... </blockquote>
==Module One: Objectives of Radiological Protection==
*impairment of reproductive capacity by either reduced fertility or fecundity (affecting birth rate, age distribution, number, and density); and
*induction of chromosomal damage. </blockquote>
==Module One: Fundamental Principles of Radiological Protection==
===[[ICRP Publication 103]] paragraph 203===
<blockquote>The principle of justification: Any decision that alters the radiation exposure situation should do more good than harm. This means that, by introducing a new radiation source, by reducing existing exposure, or by reducing the risk of potential exposure, one should achieve sufficient individual or societal benefit to offset the detriment it causes.
This means that, by introducing a new radiation source, by reducing existing exposure, or by reducing the risk of potential exposure, one should achieve sufficient individual or societal benefit to offset the detriment it causes.</blockquote>
===[[ICRP Publication 103]] paragraph 205===
<blockquote>The Commission recommends that, when activities involving an increased or decreased level of radiation exposure, or a risk of potential exposure, are being considered, the expected change in radiation detriment should be explicitly included in the decision-making process. The consequences to be considered are not confined to those associated with the radiation – they include other risks and the costs and benefits of the activity. Sometimes, the radiation detriment will be a small part of the total. Justification thus goes far beyond the scope of radiological protection. It is for these reasons that the Commission only recommends that justification require that the net benefit be positive. To search for the best of all the available alternatives is a task beyond the responsibility of radiological protection authorities.</blockquote>
===[[ICRP Publication 103]] paragraph 203===
<blockquote>The principle of optimisation of protection: The likelihood of incurring exposures, the number of people exposed, and the magnitude of their individual doses should all be kept as low as reasonably achievable, taking into account economic and societal factors. This means that the level of protection should be the best under the prevailing circumstances, maximising the margin of benefit over harm. In order to avoid severely inequitable outcomes of this optimisation procedure, there should be restrictions on the doses or risks to individuals from a particular source (dose or risk constraints and reference levels).
This means that the level of protection should be the best under the prevailing circumstances, maximising the margin of benefit over harm. In order to avoid severely inequitable outcomes of this optimisation procedure, there should be restrictions on the doses or risks to individuals from a particular source (dose or risk constraints and reference levels).</blockquote>
===[[ICRP Publication 103]] paragraph 211===
<blockquote>The process of optimisation of protection is intended for application to those situations that have been deemed to be justified. The principle of optimisation of protection, with restriction on the magnitude of individual dose or risk, is central to the system of protection and applies to all three exposure situations: planned exposure situations, emergency exposure situations, and existing exposure situations.</blockquote>
===[[ICRP Publication 103]] paragraph 212===
<blockquote>The principle of optimisation is defined by the Commission as the source related process to keep the likelihood of incurring exposures (where these are not certain to be received), the number of people exposed, and the magnitude of individual doses as low as reasonably achievable, taking economic and societal factors into account.</blockquote>
===[[ICRP Publication 103]] paragraph 203===
<blockquote>The principle of application of [[dose limits]]: The total dose to any individual from regulated sources in planned exposure situations other than medical exposure of patients should not exceed the appropriate limits recommended by the Commission.</blockquote>
===[[ICRP Publication 103]] paragraph 204===
<blockquote>Regulatory [[dose limits]] are determined by the regulatory authority, taking account of international recommendations, and apply to workers and to members of the public in planned exposure situations.</blockquote>
===[[ICRP Publication 103]] paragraph 243===
<blockquote>[[Dose limits]] apply only in planned exposure situations but not to medical exposures of patients ... Within a category of exposure, occupational or public, [[dose limits]] apply to the sum of exposures from sources related to practices that are already justified.</blockquote>
==Module Two: Exposure Categories and Situations==
<blockquote> Even if all reasonable steps have been taken during the design stage to reduce the probability and consequences of potential exposures, such exposures may need to be considered in relation to emergency preparedness and response. Emergency exposure situations are unexpected situations that may require urgent protective actions, and perhaps also longer-term protective actions, to be implemented. Exposure of members of the public or of workers, as well as environmental contamination can occur in these situations. Exposures can be complex in the sense that they may result from several independent pathways, perhaps acting simultaneously. Furthermore, radiological hazards may be accompanied by other hazards (chemical, physical, etc.). Response actions should be planned because potential emergency exposure situations can be assessed in advance, to a greater or lesser accuracy depending upon the type of installation or situation being considered. However, because actual emergency exposure situations are inherently unpredictable, the exact nature of necessary protection measures cannot be known in advance but must flexibly evolve to meet actual circumstances ... </blockquote>
==Module Two:Absorbed, Equivalent, and Effective Dose== ===[[ICRP Publication 103]] paragraphs 107, 108, and 109=== <blockquote>In radiation biology, clinical radiology, and radiological protection the absorbed dose, D, is the basic physical dose quantity, and it is used for all types of ionising radiation and any irradiation geometry. It is defined as ... the mean energy imparted to matter ... [divided by the mass]The SI unit of absorbed dose is J kg<sup>-1</sup> and its special name is gray (Gy) ... While it is defined at any point in matter, its value is obtained as an average over a mass ... Absorbed dose is a measurable quantity and primary standards exist to determine its value.When using the quantity absorbed dose in practical protection applications, doses are averaged over tissue volumes. It is assumed that, for low doses, the mean value of absorbed dose averaged over a specific organ or tissue can be correlated with radiation detriment for stochastic effects in that tissue with an accuracy sufficient for the purposes of radiological protection.</blockquote> ===[[ICRP Publication 103]] paragraph 112=== <blockquote>The protection quantities are used to specify exposure limits to ensure that the occurrence of stochastic health effects is kept below unacceptable levels and that tissue reactions are avoided. The definition of the protection quantities is based on the average absorbed dose, D<sub>T,R</sub> in the volume of a specified organ or tissue T (see Table 3), due to radiation of type R (see Table 2). The radiation R is given by the type and energy of radiation either incident on the body or emitted by radionuclides residing within it. The protection quantity equivalent dose in an organ or tissue, H<sub>T</sub>, is then defined by[[Image:Page5F1.jpg |160px]]where wR is the radiation weighting factor for radiation R. The sum is performed over all types of radiations involved. The unit of equivalent dose is J kg<sup>-1</sup> and has the special name sievert (Sv).</blockquote> ===[[ICRP Publication 103]] Table 2=== <blockquote>[[Image:Pub103T2.jpg |300px]][[Image:Pub103F1.jpg |300px]]</blockquote> ===[[ICRP Publication 103]] paragraph 101===<blockquote> ... The development of ... effective dose has made a significant contribution to radiological protection as it has enabled doses to be summed from whole and partial body exposure from external radiation of various types and from intakes of radionuclides.</blockquote> ===[[ICRP Publication 103]] paragraph 125===<blockquote>The effective dose, E, ... is defined by a weighted sum of tissue equivalent doses as:[[Image:Page5F2.jpg |225px]]where w<sub>T</sub> is the tissue weighting factor for tissue T and Σw<sub>T</sub> = 1. The sum is performed over all organs and tissues of the human body considered to be sensitive to the induction of stochastic effects. These w<sub>T</sub> values are chosen to represent the contributions of individual organs and tissues to overall radiation detriment from stochastic effects. The unit of effective dose is J kg<sup>-1</sup> with the special name sievert (Sv). The unit is the same for equivalent dose and effective dose ... Care must be taken to ensure that the quantity being used is clearly stated.</blockquote> ===[[ICRP Publication 103]] Table 3===<blockquote>[[Image:Pub103T3.jpg |300px]]</blockquote> ==Module Two: Dose limits=====[[ICRP Publication 103]] paragraph 243===<blockquote>Dose limits apply only in planned exposure situations but not to medical exposures of patients. ... dose limits ... recommended in Publication 60 ... continue to provide an appropriate level of protection. ... Within a category of exposure, occupational or public, dose limits apply to the sum of exposures from sources related to practices that are already justified ...</blockquote>
===[[ICRP Publication 103]] paragraph 247===
<blockquote>Dose limits do not apply in emergency exposure situations where an informed, exposed individual is engaged in volunteered life-saving actions or is attempting to prevent a catastrophic situation. For informed volunteers undertaking urgent rescue operations, the normal dose restriction may be relaxed ...</blockquote>
===[[ICRP Publication 103]] paragraph 248===
<blockquote>For informed individuals of the general public involved in caring and comforting patients released from a hospital following therapy with unsealed radionuclides, the normal dose restriction may be relaxed and such individuals should in general not be subject to the public dose limit ...</blockquote>
==Module Two:=[[ICRP Publication 103]] paragraph 186===<blockquote>... Once an employer has been notified of a pregnancy, additional protection of the embryo/fetus should be considered. The working conditions of a pregnant worker, after declaration of pregnancy, should be such as to ensure that the additional dose to the embryo/fetus would not exceed about 1 mSv during the remainder of the pregnancy ...</blockquote>
