5.1  Dialkyldithiocarbamates (DTCs), benzothiazoles, and thiurams are often used as vulcanization accelerators in NRL products. Zinc DTC accelerators are added either directly or are formed in situ during the vulcanization process via reaction between a thiuram(s) and zinc oxide. DTCs, benzothiazoles, and thiurams have been detected in leachates from medical devices made of rubber such as gloves. Studies have shown these chemicals can cause allergic contact dermatitis. A simple selective method to monitor rubber accelerator levels in rubber extracts would be useful for quality control, product screening and research.5.2 This colorimetric assay measures dialkyldithiocarbamates, including zinc dialkyldithiocarbamates (ZDTC), mercaptobenzothiazole (MBT) and thiurams as a total thiol vulcanization accelerator level in rubber products. A UV spectrophotometer with detection at 320 nm is used to measure the ZDTC, mercaptobenzothiazole and thiurams. Sample extracts diluted at 1:20 prior to measurement on the spectrophotometer is usually sufficient to quantify the residual accelerator level from most commercially available rubber gloves; however, sample dilution can be adjusted (from neat extract to > 1:20 dilution) based on analytical needs. Thiurams and ZDTCs complex with cobalt turning the extract to a concentration-dependent shade of green. ZDTCs reacts quickly while thiurams react very slowly (requiring a heat catalyst). Mercaptobenzothiazole does not complex to Co(III), however, it absorbs strongly at 320 nm. It can be distinguished from both ZDTCs and thiurams by its strong absorbance at 320 nm without the cobalt dependent visible green color. Cobalt complexed thiurams and ZDTCs, but not MBT, also have and absorbance at 370 nm (2).1.1 This test method is designed to quantify the amount of total extractable accelerators in natural rubber latex (NRL) and nitrile gloves. Three common classes of rubber accelerators, the mercaptobenzothiazole (MBT), thiuram, and thiocarbamate type compounds can be detected and quantified by this method. If the specific rubber accelerator(s) present in the glove material is not known, quantification is based on zinc dibutyldithiocarbamate (ZDBC) equivalents. This method will not detect all potential rubber accelerators, including mercaptobenzothiazole disulfide, dimorpholine, thioureas and diphenyl diamine.1.2 For the purpose of this test method, the range of chemical accelerator measurement is based on the limit of detection (LOD) established in the performing laboratory.1.3 This test method should be performed by experienced analysts or under the supervision of those experienced in the use of spectroscopy and working with organic solvents.1.4 This test method has not been validated for measurement of long chain dithiocarbamates or accelerators from other rubber products, such as lubricated condoms (1).2 Although this assay has been reported in the literature for the evaluation of accelerator levels in condoms, further validation for accelerator measurement from other rubber products is required by the testing laboratory prior to use.1.5 This test method is not designed to evaluate the potential of rubber materials to induce or elicit Type IV skin sensitization reactions (for Type IV skin sensitization reactions see Test Method D6355). Total extractable accelerator content does not reflect bioavailablity of individual accelerators that are detected and measured by this method. This test method should be used to test and measure the total residual chemical accelerator level in NRL and nitrile gloves under controlled laboratory conditions, and should not be used to describe, appraise, or assess the hazard or risk of these materials or products under actual in-use conditions.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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定价： 156元 / 折扣价： 133 元

PVC compounds are used in a wide variety of products and hence they are formulated to provide a wide range of physical properties. The physical properties required in a compound depend upon the product in which it is used. These properties are largely determined by the type, quantity, and quality of the compounding ingredients. The analytical test method described below makes use of infrared spectrophotometry for the qualitative or quantitative determination, or both, of many of these ingredients in PVC compounds. This test method may be used for a variety of applications including process control, raw material acceptance, product evaluation, and determination of changes in composition resulting from environmental testing.This test method is directly applicable only to those components listed in the appendix and to those components which are known to be similar in chemical composition and in solubility characteristics to the chemicals listed in the appendix.1.1 This test method provides for the identification of certain resins, plasticizers, stabilizers, and fillers in poly(vinyl chloride) (PVC) compounds by an infrared spectrophotometric technique. In many cases, individual components may be measured quantitatively. Complementary procedures, such as chromatographic and other separations, will be necessary to separate specific components and extend the applications of this test method. Other instrumental test methods, such as optical emission or X-ray spectroscopic methods, may yield complementary information which may allow more complete or, in some cases, easier measurement of the components. The resin components covered in this test method are listed in the appendix.1.2 PVC formulations are too varied to be covered adequately by a single test method. Using the following test method, many compounds may be separated into resins, plasticizers, stabilizers, and fillers. A number of components can be quantitatively measured. Many more can be identified and their concentrations estimated. By the use of prepared standards, one may determine the usefulness and accuracy of the test method for specific PVC formulations. This test method is applicable for the resin components listed in the appendix and for other components having similar chemical compositions and solubility characteristics. This test method can lead to error in cases where the nature of the components is not known.1.3 The values stated in SI units are to be regarded as the standard. The values in brackets are given for information only.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.Note 1—There is no known ISO equivalent to this standard.

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4.1 This guide is intended for use in evaluating the performance of field-portable electroanalytical or spectrophotometric devices for lead determination, or both.4.2 Desired performance criteria for field-based extraction procedures are provided.4.3 Performance parameters of concern may be determined using protocols that are referenced in this guide.4.4 Example reference materials to be used in assessing the performance of field-portable lead analyzers are listed.4.5 Exhaustive details regarding quality assurance issues are outside the scope of this guide. Applicable quality assurance aspects are dealt with extensively in references that are cited in this guide.1.1 This guide provides guidelines for determining the performance of field-portable quantitative lead analysis instruments.1.2 This guide applies to field-portable electroanalytical and spectrophotometric (including reflectance and colorimetric) analyzers.1.3 Sample matrices of concern herein include paint, dust, soil, and airborne particles.1.4 This guide addresses the desired performance characteristics of field-based sample extraction procedures for lead, as well as on-site extraction followed by field-portable analysis.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Airborne hexavalent chromium is carcinogenic (1-3),4 and analytical methods for the measurement of this species in workplace aerosols are desired. Worker exposure to hexavalent chromium occurs primarily through inhalation (1-3), and this test method provides a means for exposure assessment to this highly toxic species. Analytical results from this procedure can be used for regulatory compliance purposes (4).1.1 This test method specifies a method for the determination of the time-weighted average mass concentration of hexavalent chromium in workplace air samples.1.2 This test method is applicable to the personal sampling of the inhalable fraction of airborne particles, as defined in ISO 7708, and to area (static) sampling.1.3 The sample dissolution procedure specifies separate procedures for soluble and insoluble hexavalent chromium.1.4 This test method is applicable to the determination of masses of 0.01 μg to 10 μg of hexavalent chromium per sample without dilution.1.5 The concentration range for hexavalent chromium in air for which this procedure is applicable is approximately 0.1 μg/m3 to 100 μg/m3, assuming 1 m3 of air sample. The range can be extended upwards by appropriate dilution.1.6 Interconversion of trivalent and hexavalent chromium species may occur during sampling and sample preparation, but these processes are minimized to the extent possible by the sampling and sample preparation procedures employed.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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定价： 156元 / 折扣价： 133 元 加购物车

定价： 156元 / 折扣价： 133 元 加购物车

5.1 Hexavalent chromium is anthropogenic from a number of commercial and industrial sources. It readily penetrates biological membranes and has been identified as a carcinogen and industrial toxin. Hexavalent chromium is a known inhalation irritant and is associated with respiratory cancer (5).5.2 Ambient atmospheric concentrations of hexavalent chromium are well below the detection limits of previous analytical methods utilized for the determination of hexavalent chromium (2).5.3 Ambient atmospheric concentrations of hexavalent chromium provide a means of evaluating exposures in a manner that can be related to health-based risk levels. The data for samples collected in situ provide an improved basis for health assessments of potential exposures (5).5.4 This test method provides step-by-step instructions for the sampling and analysis of total suspended ambient air particulates for hexavalent chromium.5.5 This test method assumes that field and laboratory personnel are familiar with low volume ambient air sampling and hexavalent chromium analysis by ion chromatography with post-column derivatization. This method should not be performed for regulatory or compliance purposes until the field and laboratory personnel have demonstrated the ability to collect and analyze samples in such a manner as to pass the quality control requirements found in Section 13.1.1 This test method specifies a procedure for the sampling and analysis of airborne particulate matter for hexavalent chromium in ambient air samples.1.2 This method is applicable to the determination of masses of 0.40 to 20.0 ng of hexavalent chromium per sample without dilution. Detection limits vary by instrumentation. Some laboratories may be able to achieve lower detection limits. The lower limit of applicability for this method was determined in a 2019 multi-laboratory detection limit study (1).21.3 This method is applicable to hexavalent chromium measurement in the atmosphere from 0.019 to 0.926 ng/m3 assuming a 21.6 m3 sample volume. The lower range may be decreased with longer sampling times. The upper range can be increased using appropriate dilutions.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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定价： 754元 / 折扣价： 641 元

5.1 Failure to make such a rectification introduces differences from the true value of the spectrum of about 0.02 to 0.4 ΔE*ab units. All users are required to make a rectification of such bandpass differences. It is especially incumbent upon writers of computer programs whose function it is to acquire such spectra from instruments to see that a competent rectification is implemented in the program before any additional processing of the spectrum, or calculations involving the spectrum are accomplished, or before the spectrum is made available to a user.5.2 Legacy measuring systems are explicitly exempted from any requirements for retrofitting of hardware or software and may continue to utilize previously accepted methods of making the bandwidth rectification.1.1 This standard outlines the methods that can be used to deconvolve, at least partially, the spectral bandpass differences of raw spectral data acquired by abridged spectrophotometry. Such differences are introduced because the spectral passband must be of significant bandwidth to allow sufficient energy to reach the detector. On the other hand, the spectral data that should be reported is that of a virtual 1-nm bandwidth spectrum in order to be useful in the CIE method of tristimulus integration which involves 1-nm summation.1.2 The standard establishes practices for whether, when, and how a bandpass rectification should be made to any reflectance or transmittance spectrum acquired by abridged spectrophotometry.1.3 It is applicable where the shape of the passband is triangular and the bandwidth is equal to the measurement interval between passbands. Information is provided in Section 7 for users when that condition is not satisfactorily met.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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