Optimization of protection

The optimization of protection and safety measures, or the application of the ALARA principle (to keep doses as low as reasonably achievable, economic and social factors being taken into account), should be carried out at aU stages during the lifetime of the equipment and installations, fri the optimization, aU relevant factors should be taken into account, such as  

The trade-offs between the various factors should be considered, for example, by means of decision aiding techniques such as multicriteria methods [9, 10], 

When a structured quantitative approach seems to be appropriate for the selection of measures, the decision should result from the application of the optimization procedure. This procedure should include the following successive steps  

All relevant radiological, economic and social factors for a particular situation under review, such as the distribution of individual doses and collective doses for site personnel and the public, the impacts on future generations and the investment costs, should be identified  

All possible options for protection that may potentially reduce doses due to occupational or public exposure should be identified  

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Although use of automated oligonucleotide synthesis is widespread, work continues on the optimization of protecting groups, coupling conditions, and deprotection methods, as well as on the automated devices.56... 

Optimization of protection and safety requires that both normal and potential exposures be taken into account. Normal exposures are exposures that are expected to be received under routine and normal transport conditions as defined in para. 106 of the Regulations. Potential exposures are exposures that are not expected to be delivered with certainty but that may result from an accident or owing to an event or sequence of events of a probabilistic nature, including equipment failures and operating errors. In the case of normal exposures, optimization requires that the expected magnitude of individual doses and the number of people exposed be taken into account in addition, in the case of potential exposures, the likelihood of the occurrence of accidents or events or sequences of events is also taken into account. Optimization should be documented in the RPPs. See also Ref. [2],... 

All exposures are to be kept as low as reasonably achievable, economic and social factors being taken into account (optimization of protection). 

It should be a task of the competent anthority to ensure that all transport activities are conducted under a general framework of optimization of protection and safety. 

Although the concepts of justification of practices, optimization of protection, dose commitment, and collective dose were all already treated and considered in the ICRP Publication 9 (1965), they were explicitly expressed not until in the ICRP Publication 26 (1977). The implementation of the new approach after 50 years of stepwise development meant adaptation of a modem protection concept which in a refined and addended form is continuously iqiplicable. 

Optimization of Protection Radiation facilities must be designed and constructed as safe as practicable... 

These limits have been set particularly for workers at nuclear power plants. The operations to be carried out at a disposal facility allow for lower exposure, provided adequate technical and organizational measures are taken. Optimization of protection requires such measures to be taken. Accordingly, national regulations may set dose limits for workers in a disposal facility which are lower than the values given alrove. A sensible design target for the operation of a disposal facility is a limit for the occupational effective dose of 5 mSv per year. 

In relation to the optimization of protection. Safety Series No. 89 recommends that each practice should be assessed as if it were to be subjected to a formal optimization procedure. A study of the available options (including various kinds of regulatory action) should be made and the conclusion reached that exenption is the option that optimizes radiation protection. If, however, a... 

Radiation protection is governed by three fundamental principles that are designed to estabUsh a level of protection based on what is deemed acceptable (ICRP 2007a). These principles are justification, optimization of protection, and apphcation of dose limits. In the following, the meaningfulness of these principles in medical X-ray diagnosis-in particular, MSCT-is discussed ... 

Optimization 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 (ICRP 2007a). This means that examinations have to be optimized in order to define an acceptable balance between patient exposure and necessary diagnostic image quality. 

Further guidance on the implementation of a programme for the optimization of protection in occupational exposure is given in Refs [6, 9] and in a Safety Report on Optimization of Radiation Protection in the Control of Occupational Exposure [10]. 

The proper application of the principle of optimization of protection requires that the operating organization put in place a management structure to ensure that radiation protection is appropriately considered at all levels of the operating organization. 

Adoption of the concept of kinetic criteria allows a simple optimization of protective installation working parameters. In many cases it is unnecessary to fully retard the corrosion of a protected metal structure. Deep cathodic polarization is an expensive process. It requires the application of high power equipment, developed anodic systems, and is connected with high operation costs. For practical reasons, partial protection is sufficient in most cases, ensuring a decrease of the corrosion rate to such a level at which the assumed lifetime of the structure is attained. Evaluation of the effectiveness of cathodic protection based on a criterion taking into account the degree of decrease of corrosion process rates can become in the near future a new, important application element in the anticorrosion protection technology. 

To achieve the objectives specified in Section 3 as they relate to practices, a system of protection founded on basic principles is needed. The conceptual framework developed by the ICRP and used here includes justification of practices, optimization of protection, dose limitation and safety of sources. The dose limitation principle does not apply to medical exposures. 

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