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This specification contains reference tables that give temperature-electromotive force (emf) relationships for types B, E, J, K, N, R, S, T, and C thermocouples. These are the thermocouple types most commonly used in industry. Thermocouples and matched thermocouple wire pairs are normally supplied to the tolerances on initial values of emf versus temperature. Color codes for insulation on thermocouple grade materials, along with corresponding thermocouple and thermoelement letter designations are given. Four types of tables are presented: general tables, EMF versus temperature tables for thermocouples, EMF versus temperature tables for thermoelements, and supplementary tables.1.1 This specification contains reference tables (Tables 8 to 25) that give temperature-electromotive force (emf) relationships for Types B, C, E, J, K, N, R, S, and T thermocouples.2 These are the thermocouple types most commonly used in industry. The tables contain all of the temperature-emf data currently available for the thermocouple types covered by this standard and may include data outside of the recommended upper temperature limit of an included thermocouple type.1.2 In addition, the specification includes standard and special tolerances on initial values of emf versus temperature for thermocouples (Table 1), thermocouple extension wires (Table 2), and compensating extension wires for thermocouples (Table 3). Users should note that the stated tolerances apply only to the temperature ranges specified for the thermocouple types as given in Tables 1, 2, and 3, and do not apply to the temperature ranges covered in Tables 8 to 25.1.3 Tables 4 and 5 provide insulation color coding for thermocouple and thermocouple extension wires as customarily used in the United States.1.4 Recommendations regarding upper temperature limits for the thermocouple types referred to in 1.1 are provided in Table 6.1.5 Tables 26 to 45 give temperature-emf data for single-leg thermoelements referenced to platinum (NIST Pt-67). The tables include values for Types BP, BN, JP, JN, KP (same as EP), KN, NP, NN, TP, and TN (same as EN).1.6 Tables for Types RP, RN, SP, and SN thermoelements are not included since, nominally, Tables 18 to 21 represent the thermoelectric properties of Type RP and SP thermoelements referenced to pure platinum. Tables for the individual thermoelements of Type C are not included because materials for Type C thermocouples are normally supplied as matched pairs only.1.7 Polynomial coefficients which may be used for computation of thermocouple emf as a function of temperature are given in Table 7. Coefficients for the emf of each thermocouple pair as well as for the emf of most individual thermoelements versus platinum are included. Coefficients for type RP and SP thermoelements are not included since they are nominally the same as for types R and S thermocouples, and coefficients for type RN or SN relative to the nominally similar Pt-67 would be insignificant. Coefficients for the individual thermoelements of Type C thermocouples have not been established.1.8 Coefficients for sets of inverse polynomials are given in Table 46. These may be used for computing a close approximation of temperature (°C) as a function of thermocouple emf. Inverse functions are provided only for thermocouple pairs and are valid only over the emf ranges specified.1.9 This specification is intended to define the thermoelectric properties of materials that conform to the relationships presented in the tables of this standard and bear the letter designations contained herein. Topics such as ordering information, physical and mechanical properties, workmanship, testing, and marking are not addressed in this specification. The user is referred to specific standards such as Specifications E235, E574, E585/E585M, E608/E608M, E1159, or E2181/E2181M for guidance in these areas.1.10 The temperature-emf data in this specification are intended for industrial and laboratory use.1.11 Thermocouple color codes per IEC 584–3 are given in Appendix X1.1.12 The values stated in either SI units or inch-pound units are to be regarded separately as standard.1.12.1 The values stated in brackets are not conversions to the values they succeed and therefore shall be used independently of the preceding values.1.12.2 The values given in parentheses are conversions of the values they succeed.1.12.3 Combining values from the two systems may result in non-conformance with the standard.1.13 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.1.14 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 A microcosm test is conducted to obtain information concerning toxicity or other effects of a test material on the interactions among three trophic levels (primary, secondary, and detrital) and the competitive interactions within each trophic level. As with most natural aquatic ecosystems, the microcosms depend upon algal production (primary production) to support the grazer trophic level (secondary production), which along with the microbial community are primarily responsible for the nutrient recycling necessary to sustain primary production. Microcosm initial condition includes some detritus (chitin and cellulose) and additional detritus is produced by the system. The microcosms include ecologically important processes and organisms representative of ponds and lakes, but are non-site specific. To the extent possible, all solutions are mixtures of distilled water and reagent grade chemicals (see Section 8) and all organisms are available in commercial culture collections.5.2 The species used are easy to culture in the laboratory and some are routinely used for single species toxicity tests (Guide E729; Practice D3978, Guides E1192 and E1193). Presumably acute toxicity test results with some of these species would be available prior to the decision to undertake the microcosm test. If available, single species toxicity results would aid in distinguishing between indirect and direct effects.5.3 These procedures are based mostly on published methods (4-6), interlaboratory testing (7-10, 11), intermediate studies (12-23, 24), statistical studies (25-27) and mathematical simulation results (28). Newer studies on jet fuels have been reported (29)(See 15.1 for multivariate statistical analyses) and on the implications of multispecies testing for pesticide registration (30). Environmental Protection Agency, (EPA) and Food and Drug Administration, (FDA) published similar microcosm tests (31). The methods described here were used to determine the criteria for Acceptable Tests (Section 16). Additional papers have been published using this method for measuring chemical stress on organisms (32).5.4 Concurrent to measuring the ecological effects, it is advisable to measure the concentration of the parent test chemical, and if possible, the transformation products ((33) see Section 12). The concentrations can be measured on either the same microcosms or on concurrent replicates. Information on the chemical concentrations of parent material and transformation products would aid in the assessment of chemical persistence, exposure, accumulation, and in interpreting, if recovery is associated with chemical degradation or biological adaptation. This protocol deals only with ecological effects, because the techniques for fate studies are in general usage.5.5 In the microcosm, as in natural ecosystems, a population must be able to obtain its requirements from the products of other trophic levels, to maintain a birth rate equal to or greater than its death rate, and to support populations of organisms that will remove its waste products. As in natural ecosystems, several organisms might be capable of fulfilling the same function, and shifts in species dominance can occur without disruption of an ecological process. However, species that are “ecological equivalents” in one function might not be “equivalent” in other functions; for example, a filamentous alga and a single cell alga might equally produce O2, remove NO3, NH3, and PO4, but differ in the type of grazer populations they can sustain, for example, filamentous alga might support amphipods whereas unicellular algae might support Daphnia.5.6 Results of these microcosm tests might be more likely to be indicative of natural ecosystem responses to chemicals than single species toxicity tests because microcosm tests can indicate the explosive population increases that might occur in a community when more sensitive competitors or predators are eliminated or the food supply is increased through competitive interactions. Also, microcosm tests are more likely to display the effects of chemical transformation or increased exposure to certain organisms by means of concentration of parent or degradation products in their food source or habitat.5.7 A list of potential ecological effects is provided to serve as a summary (see Annex A1).5.8 The microcosm test can also be used to obtain information on the toxicity or other effects of species or strains, not included in the control inocula (13). Additional modifications might be required.5.9 Explicit Limitations of the Aquatic Microcosm Protocol: 5.9.1 The scope of the test is limited in the following respects:5.9.1.1 No fish or other vertebrates are included,5.9.1.2 Predation on Daphnia is extremely limited or absent,5.9.1.3 The ecosystem becomes nutrient limited,5.9.1.4 The inocula are not gnotobiotic and aseptic technique is not used (except in maintaining stock cultures of microorganisms). Contaminating microorganisms are likely to be introduced with the larger organisms and during sampling.5.9.1.5 Most detrital processing is carried out by the sediment microbial community, but this community is not clearly described or measured by this protocol.5.9.2 Extrapolation to natural ecosystems should consider differences in community structure, limiting factors, and water chemistry (see Section 17).1.1 This practice covers procedures for obtaining data concerning toxicity and other effects of a test material to a multi-trophic level freshwater community, independent of the location of the test.1.2 These procedures also might be useful for studying the fate of test materials and transformation products, although modifications and additional analytical procedures might be necessary.1.3 Modification of these procedures might be justified by special needs or circumstances. Although using appropriate procedures is more important than following prescribed procedures, results of tests conducted using unusual procedures are not likely to be comparable to results of many other tests. Comparison of results obtained using modified and unmodified versions of these procedures might provide useful information concerning new concepts and procedures for conducting multi-trophic level tests.1.4 This practice is arranged as follows:  Section   Referenced Documents 2Terminology 3Summary of Practice 4 5Apparatus 6 Facilities 6.1 Container 6.2 Equipment 6.3Hazards 7Microcosm Components 8 Medium 8.1 Medium Preparation 8.2 Sediment 8.3 Microcosm Assembly 8.4Test Material 9 General 9.1 Stock Solution 9.2 Nutrient Control 9.3Test Organisms 10 Algae 10.1 Animals 10.2 Specificity of Organisms 10.3 Sources 10.4 Algal Culture Maintenance 10.5 Animal Culture Maintenance 10.6Procedure 11 Experimental Design 11.1 Inoculation 11.2 Culling 11.3 Addition of Test Material 11.4 Measurements 11.5 Reinoculations 11.6Analytical Methodology 12Data Processing 13Calculations of Variables from Measurements 14Statistical Analyses 15Acceptability of Test 16Interpretation of Results 17Report 18Annex Annex A1Appendices   Relationship of Media Appendix X1 Statistical Guidance Appendix X21.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.6 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.Specific hazard statements are given in Section 7.1.7 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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