Maximum permissible addition

Amended EQS = Background concentration + Maximum permissible addition (MPA)... 

The presence of residual unbound transition-metal ions on a dyed substrate is a potential health hazard. Various eco standards quote maximum permissible residual metal levels. These values are a measure of the amount of free metal ions extracted by a perspiration solution [53]. Histidine (5.67) is an essential amino acid that is naturally present as a component of perspiration. It is recognised to play a part in the desorption of metal-complex dyes in perspiration fastness problems and in the fading of such chromogens by the combined effects of perspiration and sunlight. The absorption of histidine by cellophane film from aqueous solution was measured as a function of time of immersion at various pH values. On addition of histidine to an aqueous solution of a copper-complex azo reactive dye, copper-histidine coordination bonds were formed and the stability constants of the species present were determined [54]. Variations of absorption spectra with pH that accompanied coordination of histidine with copper-complex azo dyes in solution were attributable to replacement of the dihydroxyazo dye molecule by the histidine ligand [55]. 

The special process feature for case 3 is a relatively high reaction enthalpy in combination with a low maximum permissible temperature Texo- An alternative safety solution would be to control both these two parameters. For example by adding a pump to the reactor and with solvent makeup the process can be made continuous (CSTR). This allows the adoption of a higher maximum permissible temperature Texo, because of the short residence time and the dilution effect, and a reduction of the adiabatic temperature increase ATadiab because of the dilution effect. Such a (drastic) process and facility change will always require an iterative safety-technical reaction PHA furthermore additional may become necessary. 

Maximum allowable working pressure (MAWP) The maximum permissible gauge pressure of a vessel in its operating position at a designated temperature. The pressure is based on calculations for each element in a vessel, using nominal thickness exclusive of additional metal thickness allowed for corrosion. The MAWP is the basis for the upper limit of pressure setting of the safety relief devices that protect the vessel (see Section 3.6). 

Table 11.7 Maximum permissible concentrations of potentially toxic elements (PTEs) in soil after application of sewage sludge and maximum annual rates of addition (modified from DoE, 1996)...

Maximum permissible average annual rate of PTE addition over a... 

EPA has set the maximum permissible level of benzene in drinking water at 5 parts per billion (ppb). Because benzene can cause leukemia, EPA has set a goal of 0 ppb for benzene in drinking water and in water such as rivers and lakes. EPA estimates that 10 ppb benzene in drinking water that is consumed regularly or exposure to 0.4 ppb benzene in air over a lifetime could cause a risk of one additional cancer case for every 100,000 exposed persons. EPA recommends a maximum permissible level of benzene in water of 200 ppb for short-term exposures (10 days) for children. 

In 1946, a maximum permissible concentration was added for hexavalent chromium. The use of the salts of barium, hexavalent chromium, heavy metal glucosides, and other substances were prohibited in water treatment processes. In addition, the 1946 standards authorized the use of the membrane filter procedure for bacteriological examination of water samples. 

In addition to different column characteristics, one more factor must be taken into consideration in gas chromatography, namely the sample capacity. This is defined as the maximum permissible sample size that can be injected into a column without more than 10% loss of efficiency, and it is expressed as... 

While the amounts of nitrate could be certified in rainwater CRMs [3], their certification in freshwater CRMs was not possible owing to the stabilisation procedure used (involving an addition of nitric acid) [2]. Consequently, it was decided to organize a separate interlaboratory study of which the final aim was to produce artificial freshwater CRMs certified for their contents of nitrate, one with a low nitrate content (CRM 479) and one with a high nitrate content (CRM 480) [4,5]. These CRMs correspond to values below and slightly above the maximum permissible nitrate content (approx. 50 mg L" ) mentioned in the Drinking Water Directive. 

For the lower portion of tall towers, where the combined axial stress controls the design of the shell, there is the problem of selecting the maximum allowable axial compressive stress. The combined axial tensile stress presents no problem. The tensile stresses produced by internal pressure, bending stress of wind loads or bending stress firom seismic loads may be combined by simple addition of the stresses. The thickness of the shell may be calculated so that the combination of axial tensile stresses is equal or less than the maximum permissible value specified by the ASME Code. 

Atrazine was not the only chemical to be banned - the sale and use of alachlor on soya was also prohibited. In addition, maximum permissible doses of several chemicals were reduced significantly (seeZanin etal., 1991). 

It is obvious that this is commercially impossible for the industrial production of bulk chemicals such as butanal or a-alkenes, since additional manufacturing costs of cents (or even fractions of cents) per kilogram are prohibitive. The maximum permissible burden for fine chemicals might be higher, and may render this equipment possible for realization of new ideas about the recycling of multiphase catalysts. 

Various phenylarsoiuc acids - especially arsanilic acid, sodium arsanilate, and 3-nitro-4-hydroxyphenylarsonic acid-have been used as feed additives for disease control and for improvement of weight gain in swine and poultry for more than 50 years. The arsenic is present as As" " and is rapidly excreted present regulations require withdrawal of arsenical feed additives 5 days before slaughter for satisfactory depuration. Under these conditions, total arsenic residues inedible tissues do not exceed the maximum permissible limit of 2.0 mg/kg FW. Organoarseiucals probably will continue to be used as feed additives unless new evidence indicates otherwise. 

As a final note on PVC, it is worth mentioning Vinyl 2010, which is an EU voluntary commitment study on the PVC industry initiated in 2001 for the following 10 years, including mid-term revisions of targets in 2005 and definition of new objectives in 2010. The plan includes for full replacement of lead stabilisers by 2015, in addition to the replacement of cadmium stabilisers by March 2001 [27, 30]. Also in Vinyl 2010, the following values are put forward for maximum permissible VCM concentrations in the final PVC products ... 

It is seen from equation (3) that the optimum velocity is directly related to the solute diffusivity and thus, to the temperature. It follows that increasing the temperature, increases the optimum velocity and thus provides the same efficiency but with shorter analysis time. However, the choice of operating temperature can be somewhat complicated. It will be seen later that there is a temperature at which the two enantiomers co-elute and, at the co-elution temperature, separation is impossible. As a consequence, the operating temperature must be chosen significantly above, or below, the coelution temperature to provide adequate selectivity. In addition, the operating temperature must also be below the maximum permissible for the particular stationary phase, as above this temperature the stationary phase degrades. 

The gate usually produces a mark on the finished molding. Naturally, this mark should not occur in an especially visible part of the article. At the same time, however, there is a limit to the allowable complexity of the numer system s design. This is also a function of the maximum permissible flow-path length for the plastics material chosen, or the additional loss of material caused by a larger runner system. For these reasons, the position of the cavity within the mold is also subject to restrictions in some cases. Other limitations with the position of mold cavities arise from the ease, with which the molded article can be removed fi om the mold, without suffering damage. 

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