Justification principle

A practice which entails or that could entail exposure to radiation should only be adopted if it yields sufficient benefit to the exposed individuals or to society to out-weigh the radiation detriment it causes or could cause (justification principle). 

As an example of the latter category, he indicated that a former radium luminising operation could be dealt with as a practice, but if contamination were discovered, which was the result of some previous radium operation whose owners were not known, it might be considered as an intervention situation. He summarised ICRP Principles for practices (justification, optimisation and dose/risk limits and constraints) and for intervention (justification and optimisation). He pointed out that dose limits may be counter-productive for intervention, because this could limit the justification principle. The underlying philosophy is to do more good than harm. 

It should be noted that the justification principle applies to a practice as a whole and not separately to its component parts, such as the disposal of waste. This means that material that is contaminated as a consequence of a practice is disposed of as a matter of optimization of protection, rather than justification. One of the purposes for which the activity concentration values have been estabhshed is to permit material in bulk quantities to be exempted or cleared from a justified practice without further consideration. 

Such effects principally cannot be observed in multi band detectors such as a UV diode array detector or a Fourier transform infrared (FTIR) detector because all wavelengths are measured under the same geometry. For all other types of detectors, in principle, it is not possible to totally remove these effects of the laminar flow. Experiments and theoretical calculations show (8) that these disturbances can only be diminished by lowering the concentration gradient per volume unit in the effluent, which means that larger column diameters are essential for multiple detection or that narrow-bore columns are unsuitable for detector combinations. Disregarding these limitations can lead to serious misinterpretations of GPC results of multiple detector measurements. Such effects are a justification for thick columns of 8-10 mm diameter. 

Economists differ widely in their views on the practical importance of these market failures, on what remedies are appropriate, and whether governments can satisfactorily remedy the problem. One clear principle is that the problem be identified as precisely as possible and the assistance be targeted as closely as possible to the problem. For example, if information is inadequate, providing knowledge about options would be preferable to aiding a specific option. The three justifications for subsidies set a minimum test of aid that many programs fail to pass. 

When a two- or higher-phase system is used with two or more phases permeable to the solute of interest and when interactions between the phases is possible, it would be necessary to apply the principle of local mass equilibrium [427] in order to derive a single effective diffusion coefficient that will be used in a one-equation model for the transport. Extensive justification of the principle of local thermdl equilibrium has been presented by Whitaker [425,432]. If the transport is in series rather than in parallel, assuming local equilibrium with equilibrium partition coefficients equal to unity, the effective diffusion coefficient is... 

It must be noted that there are a number of more or less arbitrary assumptions made in this work30,31 which need justification, as well as parameters whose values should be calculated rather than assumed. For instance, the importance of the distance dl9 taken as equal to Rc, has been mentioned. In principle, the value of this distance is a consequence of the forces between components of the metal and molecules of solvent, and would be calculated in a consistent model of the complete interface. This was pointed out by Yeager,18 who noted that the electron density tail of the metal determines the distance of closest approach of solvent in the interface, as well as the behavior of the solvent dipoles on the surface. Since changing qM will move the electron density tail in and out, dx should depend on the state of charge of the interface. In fact, it turns out31 that if dx varies linearly with surface charge according to... 

That is certainly one solution. To measure for many short time intervals and average together the readings certainly is, in principle, another solution, but one that we cannot find a justification for. Perhaps some of our readers knows of, or can do a thought experiment to come up with a scenario that would require many separate short data collection sessions that would provide data that could be averaged as we describe, but does not allow for a single protracted measurement. 

Classical mechanics which correctly describes the behaviour of macroscopic particles like bullets or space craft is not derived from more basic principles. It derives from the three laws of motion proposed by Newton. The only justification for this model is the fact that a logical mathematical development of a mechanical system, based on these laws, is fully consistent... 

This technique has the advantage that no particular measure of the reaction rate has to be chosen nor any form assumed for the change of parameter with time, but it can only be used if the curves at different temperatures are of the same form. In principle, other relationships between the shift factors and temperature could be fitted on an empirical basis but, with no theoretical justification, particular caution would be advised with extrapolation. 

As a general observation, the author s interactions with companies have led to the impression that there is a great deal of mystique associated with regulatory authorities by some companies. Every possible issue and detail are hyper-analyzed by those companies and what can be quite minor issues are invested with a significance out of proportion to their actual importance. What is important to assessors is that the development program of a specific product is logical, scientifically robust, and appropriate to the indication and patient population in question. Submission documents should be explicit, concise, and to the point with all the important issues addressed. Any omissions or deficiencies should be addressed and a robust justification for any deviations from the relevant guidelines should be provided. If these very basic principles are followed, applicants should not encounter problems with their submissions, provided, of course, the product is fit for purpose and has been proven to be of acceptable quality, safety, and efficacy. 

Justification for dividing the light scattered by large particles into diffracted, reflected, and transmitted components is provided by the localization principle (van de Hulst, 1957, pp. 208-214) whereby the terms in the Mie series are associated with each of these components. 

The mechanical philosophy now provided a new justification for the philosophical inability to isolate the elements. Bodies combined with one another because of some kind of attractive force, and the strongest such attraction would be between the two principles which combined to form a mixt. The force between two mixts would be much smaller because much of that attractive force had been used up, so to speak, in forming the mixts themselves. Thus there came to be a rule that the more compounded a body was, the easier it would be to decompound it. Running that rule in the other direction, the simpler a body was, the harder it would be to decompound it further. The only way to decompound a mixt containing only two principles, was to offer another mixt with which the principles in the first could exchange partners. There was nothing that could take one principle from another and leave it in isolated state. Whatever the origin of this idea, it readily served as a mechanistic rationalization for what had been the traditional view from Aristotelian times, that the elements cannot be isolated in material reality. 

It should be noted that the classic formulation of the harm principle by Mill refers to actions of individuals and that it is with the individual that both liberal justifications for the harm principle are concerned. The principle is justified by the need to protect the rights of individuals to live according to their own beliefs,... 

At the moment all pharmaceutical regulators choose the first horn of the dilemma and prioritize their own national populations. However, it is very difficult to find a principled justification for this. 

The importance of the wide acceptance of the three principles lay not in any permanent value this theory possessed, but in that this acceptance was a distinct break with ancient authorities and appealed to experience for its justification, and opened the way for further development on the basis of wider future experience. 

All calculations of visoelastic properties described here apply in principle only to dilute solutions, since no allowance for intermolecular interactions has been made. Nevertheless, the Rouse model in particular has been widely applied to concentrated systems. There is probably no fundamental justification for such an application. One simply assumes that each chain responds independently to the systematic motions of a medium which is composed of other chains and solvent, and which is taken to be a homogeneous Newtonian liquid (109). The contribution of the chains to the stress are taken to be additive. 

The ideal scale, as defined by (2.7a, b), also has an entirely different (and quite surprising ) theoretical basis, related to the maximum efficiency of machines and the second law of thermodynamics. This alternative definition of T(suggested by Kelvin) will be discussed in Section 4.5. However, we can recognize at this point that such a dual connection to fundamental thermodynamic principles of great universality gives (2.7a, b) a double-justification to be considered the true temperature scale. We henceforth adopt this definition of T throughout this book. 

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