PERMISSIBLE USES

These models employ continuous, rather than single event, simulation. The advantage is that continuous output can be analyzed statistically. The user can obtain answers to questions such as "For what fraction of time will the concentration of X be above Y mg/1 at point Z in the system " Or, "What danger does chemical X pose to species A at locations B and C ". These are the kinds of answers needed if he is to make rational decisions regarding the permissible uses of chemicals for agricultural purposes. 

Figure 2.10 ESR spectra of o-, m-, and p-xylene radical anions (see text for assignment of spectra). Spectrum (a) was simulated with permission using hyperfine parameters from Ref. 17b, copyright (1964) American Institute of Physics spectra (b) and (c) were simulated with permission using hyperfine parameters from ref. 17a, copyright (1961) Taylor and Francis (www.tandk. co.uk).

In polymerization kinetics, the PSSA has alternately been justified and used on the one hand, and cautioned against and avoided on the other, usually at a great expense of time on the part of the investigator, computer, and reader. In the latter case, one gets the impression that this is caused more by the unpalatability of its usual formulation, as indicated above by Aris, than to its real failure in cases of interest. Most workers who have considered specific systems feel that it holds for free radical polymerization over all but the shortest transients. A criterion for its permissible use was derived by Bamford et al. (4). 

Companies would need to apply the substitution principle under the Chemical Agents Directive when selecting substances identified as meeting the criteria safe or permissible uses. 

As a first step, relevant consumer uses would need to be listed (listed uses). Safe and permissible uses would then be removed from subsequent EU regulatory risk reduction processes12. While companies must follow recommendations, regulatory risk reduction may deem it necessary to supplement these with more prescriptive duties. 

Unless criteria for establishing safe and permissible uses need to be reviewed. 

A simplified set of registration data requirements would be demanded for safe or permissible uses14 using a basic tick box approach . Safe uses would not be subject to further risk management under REACH unless evidence indicated that registered data are incorrect. Permissible uses would not be prioritised for evaluations or other decision-making, and would be issued with time-limited exceptions during restriction and authorisation. 

Substances that provide certain safety or utility functions (permissible uses) Colours in warning signs processing chemicals for pharmaceuticals Permissible uses should not have been prioritised for evaluations or other decision-making, and could even be issued with time-limited exceptions to restriction or authorisation. A company should be able to identify whether specific uses meet these demands prior to registration. 

Safe use exceptions could apply to any use that does not result in significant contributions to environmental risks resulting from specific (i.e., point) sources. Equally, safe use exceptions to risk reduction decision-making would limit the number of consumer or professional uses subject to any given risk reduction strategy. This would apply to most industrial uses of the substances reviewed under the official EU risk assessment reports. The systems framework would therefore have avoided the need first for industry to report and then for regulators to review this information. The concept of permissible uses appears particularly relevant for the use of NP and NPE in spermicides and the use of penta-BDE in aircraft emergency evacuation systems [515]. 

The systems framework proposed that these permissible uses would have low priority... 

The following is the forward Fourier transform routine FOUR1 from J. C. Sprott, "Numerical Recipes Routines and Examples in BASIC", Cambridge University Press, Copyright (C) 1991 by Numerical Recipes Software. Used by permission. Use of this routine other than as an integral part of the present book requires an additional license from Numerical Recipes Software. 

The process is slow except at high temperatures. Considering unreinforced resins hrst, absorption causes dimensional changes and softening, that is, a reduction in surface hardness and in modulus. The glass transition temperature and associated heat distortion temperature of the resin fall substantially, lowering the maximum permissible use temperature of the resin [23]. 

I also hereby certify that this report request and the above applicant s release notice meet the definition of permissible uses" of state motor vehicle records under the provisions of the Driver s Privacy Protection Act of 1994 (Public Law 103-322, Title XXX, Section 300002(a)). 

Non-toxic materials The toxicity status of resins and additives used for food contact and packaging changes frequently, and in many cases percentages and conditions of end use are stipulated. Therefore, we do not attempt to hst such materials here. The current statuses of resins, plasticizers, stabilizers, and other additives with respect to their permissible use in contact with food ( indirect additives ) are spelled out in detail in the Code of Federal Regulations (CFR), Title 21 (Food and Drugs), Parts 173-184. The Code is reprinted annually in book form and updated weekly by the Federal Register, where one should check for the latest word on any particular substance. 

Figure 6. Typical calculated X-band EPR spectra of Cr(III) coitqjlexes (a) an octahedral, isotropically substituted Cr(III) complex (g = gyy= gzz= 1-987 D = E = 0.000 cm ) and (b) a strongly distorted octahedral Cr(III) complex (ga = 1.987 gy, = g =1.865 D = 0.490 cm" E = 0.163 cm" ) [76]. Published spectra were digitized with permission using the WinDIG software [119].

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