Substance-specific Concentration Limits

The general concentration limits are only valid if no specific values are laid down in annex I of EC Directive 67/548/EEC [3-1]. In annex I, specific concentration limits are usually fixed if the general limit values are not appropriate for the special substance. Therefore lower as well as higher limit concentrations can be found. In the first case, the substance has a more severe effect in comparison with the standard, and in the second case a less severe effect. On the basis of these concentration limits, an additional assessment of the actual effect of a substance can be done. 

3 Classification Calculation for Substances with Different Dangerous Ingredients 

If a preparation consists of different substances with hazardous properties, the calculation of the additive properties cannot be done by direct comparison of the concentration Hmits with the general classification limits mentioned in Tables 3-16 to 3-19. 

The calculation has to be by an evaluated summation of the concentrations of the ingredients. In this summation equation, substances have to be taken into consideration when their concentrations are equal to or greater than those given in Tkble 3.24. Of course, if lower values are determined in annex I, these values have to be used. 

A preparation has to be classified as very toxic if the sum of the quotients of the concentrations of the very toxic substances divided by their classification limits is equal or greater than one (see Fig. 3.25). 

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Additionally, annex I contains substance-specific concentration limits for the classification of preparations, which must be applied instead of the common concentration limits of the Dangerous Preparation Directive 1999/45/EC [3-2]. 

First of all the substance-specific concentration limits of annex I of Directive 67/548/EEC have to be used with regard to the current ATP. 

If no substance-specific concentration limits are fixed, the universal concentration limits of annex II of Directive 1999/45/EC have to be used. 

The use of 1 per cent as the concentration limit for classification of non-gaseous preparations (or 0.2 per cent for gaseous preparations) with respect to respiratory hypersensitivity is somewhat arbitrary, and it is feasible that some relatively potent substances present at levels below this limit may still be able to induce asthma. In these circumstances, scientific evidence that the standard concentration limit (i.e. 1 per cent) is inappropriate for protective purposes can be used to set a limit that is specific to the chemical—there is space in the Annex 1 entry for each substance for any such specific concentration limit. There may also be concern that subjects who are already sensitized would be unlikely to be protected by a 1 per cent limit from an asthmatic reaction provoked by the substance, since it is thought that provocation can occur at much lower... 

Preparations share the classifications used for substances, but the allocation is dependent either on the results of tests (except for those aimed at carcinogenic, mutagenic, and reprotoxic endpoints) or upon calculations using concentration limits. Unless specific concentration limits are given when the EU agrees the environmental classification for a substance, default concentration limits apply. Those which will apply when the Directive is amended are summarised in Table 6.8. 

Specify rules for applying the concentration limits, such as the sum-of-fractions rule for waste that contains mixtures of substances that cause stochastic effects (NRC, 1982a) and the rules for combining risk indexes for mixtures of substances that cause deterministic effects taking into account the substance-specific organs or tissues at risk. 

QMcaic means the maximum allowable concentration of the substance in the polymer that will not exceed the specific migration limit in the food for given time and temperature storage conditions. 

As noted in the Classification of hazardous substances and mixtures (see Chapter 1.3), there may be some cases when the available hazard data may justify classification on the basis of other cut-off values/concentration limits than the generic ones specified in the health and environment hazard class chapters (Chapters 3.2 to 3.10 and 4.1). When such specific cut-off values are used for classification, they should also apply to the obligation to compile an SDS. 

Following the establishment of specificity, the method(s) should be validated to allow for use in release and stability testing. Such validation is typically less stringent than for final methods (sec Chapter 12), but should demonstrate specificity, linearity, range, accuracy, and analysis repeatability for the API. For related substances, specificity should be demonstrated and the limit of detection (LOD) and limit of quantitation (LOQ) should be established for the API to serve as surrogate values for the LOD and LOQ of impurities for which authentic substances are not available. To achieve a sufficient LOD and simultaneously keep the API in the linear dynamic range of the detector, it may be necessary to use different sample concentrations for the analyses of the API and related substances. It is additionally beneficial to repeat the separation on new columns from different batches to ascertain that the separation obtained can be maintained column to column. 

The provisions may be related to concentration limits for the substance in a preparation or a product (e.g. emission limit for nickel in jewellery). There are also requirements for specific labelling and other safety measures (e.g. asbestos). A special mechanism for risk reduction in the Directive, that links the directive with Council Directive 67/548/EEC is provid by the 14th amendment in 1994. This Mlows substances classified as carcinogenic, mutagenic or toxic to reproduction (category 1 and 2) to be banned for consumer use. 

In most situations it remains necessary to rely on other alternatives. The most rec-ommendable method to prevent the occurrence of dust explosions is inertization. Some details to be observed in its application will be presented in Section 7.4. At this point, some general remarks shall just be made. The highest allowable oxygen concentration is substance specific. Experimental methods for the determination of this limit concentration are well known. In a first approximation it may be assumed, however, that the oxygen limit concentration for organic powders and dusts will not be lower than 8%. For metal dusts this value has to be halved. 

By definition, an explosion is a very fast proceeding oxidation reaction. Prerequisites are the prevalence of a concentration of the flammable substance within specific explosion limits, a high dispersion of the fuel in the oxidizing medium and the presence of an effective ignition source. 

To determine the classification of preparations with respect to their health and environmental effects, the substance-specific or universal concentration limits have to be used ... 

If the concentration of a non-additive property exceeds the universal or substance-specific limit, a direct classification is appropriate. 

Some of the model 5(e) orders have provisions for new chemical exposure limits, (NCELs) that can be implemented instead of using respirators to limit risks from inhalation of the PMN substance. NCELs are specific numerical limits on the airborne concentrations of the PMN substance. The EPA may develop a maximum concentration for eight hour exposures, a maximum concentration for work shifts that are shorter or longer than eight hours, and a short term exposure limit (STEL) for fifteen minute exposure periods. In order to use NCELs instead of respirators, the signatory must develop a sampling and analytical plan and have it verified by an independent third party laboratory. As of 2002 the EPA had developed thirty four NCELs. ... 

Pollutants. The problems posed by ak pollutants are very serious. Within a museum, measures can be taken to remove harmful substances as efficiently as possible by means of the installation of appropriate filter systems in the ventilation equipment. Proposed specification values for museum climate-control systems requke filtering systems having an efficiency for particulate removal in the dioctyl phthalate test of 60—80%. Systems must be able to limit both sulfur dioxide and nitrogen dioxide concentrations <10 /ig/m, and ozone to <2 /ig/m. ... 

The concentration of the flavor in the dentifrice and the nature of substances added to bring out specific flavor notes and thereby make the flavor unique are significant concerns. The flavor must not be excessive it must not bum too strongly. Also, the flavor must not be a sensitizer. Synthetic sweeteners are usually added, although regulatory concerns limit their selection for example, cyclamate [100-88-9] is not used in the United States. 

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