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4.1 This guide is intended to aid the equipment manufacturer, installer, service company, and turbine operator in coordinating their efforts to obtain and maintain clean lubrication and control systems.4.2 The flushing and cleaning philosophies stated in this guide are applicable to both large and small lubrication systems.4.3 Clean lubrication systems result from proper system design and good planning, execution, and communication by all involved during commissioning. No phase of these procedures should be undertaken without a thorough understanding of the possible effects of improper system preparation. The installation, cleaning, and flushing of the equipment should not be entrusted to persons lacking in experience.4.4 Because of the knowledge and specialized equipment that is required, the operator may wish to employ an outside specialist contractor for the system flushing. Review of this guide can provide guidelines for discussion with prospective contractors.1.1 This guide covers types of contaminants, oil purification devices, contamination monitoring, contamination control during building or refurbishing of turbine systems, lubrication system flushing, and maintenance of pure lubrication oil.1.2 To obtain maximum operating life and reliability, or lubricants and system, it is vital that the turbine lubrication system has pure oil. This guide is intended to aid the equipment manufacturer, installer, and turbine operator in coordinating their efforts to obtain and maintain clean lubrication and control systems. These systems may be on land or marine turbine generators and propulsion and mechanical drive equipment. This guide is generalized due to variations in the type of equipment, builder's practices, and operating conditions.1.3 This guide primarily addresses petroleum based lubricating oil. For systems using nonpetroleum based fluids, this guide may not be appropriate. For nonpetroleum products, consult the equipment and fluid manufacturers.1.4 This guide is applicable to both large and small lubrication systems. Some equipment specified herein, however, may not be appropriate for all systems. Moreover, in situations where specific guidelines and procedures are provided by the equipment manufacturer, such procedures should take precedence over the recommendations of this guide.1.5 This standard does not purport to address 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 The quantitative determination of hindered phenol and aromatic amine antioxidants in a new turbine oil measures the amount of these compounds that has been added to the oil as protection against oxidation. Beside phenols, turbine oils can be formulated with other antioxidants such as amines which can extend the oil life. In in-service oil, the determination measures the amount of original (hindered phenol and aromatic amine) antioxidants remaining after oxidation has reduced its initial concentration. This test method is not designed or intended to detect all of the antioxidant intermediates formed during the thermal and oxidative stressing of the oils, which are recognized as having some contribution to the remaining useful life of the in-service oil. Nor does it measure the overall stability of an oil, which is determined by the total contribution of all species present. Before making final judgment on the remaining useful life of the in-service oil, which might result in the replacement of the oil reservoir, it is advised to perform additional analytical techniques (as in accordance with Test Methods D6224 and D4378; see also Test Method D2272), having the capability of measuring remaining oxidative life of the in-service oil.5.1.1 This test method is applicable to non-zinc type of turbine oils as defined by ISO 6743 Part 4, Table 1. These are refined mineral oils containing rust and oxidation inhibitors, but not antiwear additives.5.2 The test is also suitable for manufacturing control and specification acceptance.5.3 When a voltammetric analysis is obtained for a turbine oil inhibited with a typical synergistic mixture of hindered phenol and aromatic amine antioxidants, there is an increase in the current of the produced voltammogram between 8 s to 12 s (or 0.8 V to 1.2 V applied voltage) (see Note 1) for the aromatic amines, and an increase in the current of the produced voltammogram between 13 s and 16 s (or 1.3 V to 1.6 V applied voltage) (see Note 1) for the hindered phenols in the neutral acetone test solution (Fig. 1: x-axis 1 s = 0.1 V). Hindered phenol antioxidants detected by voltammetric analysis include, but are not limited to, 2,6-di-tert-butyl-4-methylphenol; 2,6-di-tert-butylphenol; and 4,4'-Methylenebis (2,6-di-tert-butylphenol). Aromatic amine antioxidants detected by voltammetric analysis include, but are not limited to, phenyl alpha naphthylamines, and alkylated diphenylamines.NOTE 1: Voltages listed with respect to reference electrode. The voltammograms shown in Figs. 1 and 2 were obtained with a platinum reference electrode and a voltage scan rate of 0.1 V/s.FIG. 2 Hindered Phenol Voltammetric Response in Basic Test Solution with Blank Response ZeroedNOTE 1: x-axis = time (seconds) and y-axis is current (arbitrary units) with top line in Fig. 2 showing the fresh oil.5.4 For turbine oil containing only aromatic amines as antioxidants, there will only be an increase in the current of the produced voltammogram between 8 s to 12 s (or 0.8 V to 1.2 V applied voltage) (see Note 1) for the aromatic amines, by using the neutral acetone test solution (first peak in Fig. 1).5.5 For turbine oils containing only hindered phenolic antioxidants, it is preferable to use a basic alcohol test solution rather than the neutral acetone test solutions, as there is an increase in the current of the produced voltammogram between 3 s to 6 s (or 0.3 V to 0.6 V applied voltage) (see Note 1) in basic alcohol test solution (Fig. 2: x-axis 1 second = 0.1 V) in accordance with Test Method D6810.1.1 This test method covers the voltammetric determination of hindered phenol and aromatic amine antioxidants in new or in-service type non-zinc turbine oils in concentrations from 0.0075 % by mass up to concentrations found in new oils by measuring the amount of current flow at a specified voltage in the produced voltammogram.1.2 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.1.3 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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4.1 This test method and Test Method D3703 measure the same peroxide species (primarily hydroperoxides) in aviation fuels.4.2 The magnitude of the hydroperoxide number is an indication of the quantity of oxidizing constituents present. Deterioration of fuel results in the formation of hydroperoxides and other oxygen-carrying compounds. The hydroperoxide number measures those compounds that will oxidize potassium iodide.4.3 The determination of the hydroperoxide number of fuels is significant because of the adverse effect of hydroperoxides upon certain elastomers in the fuel systems.1.1 The test method covers the determination of the hydroperoxide content of aviation turbine fuels. The test method may also be applicable to the determination of the hydroperoxide content of any water-insoluble, organic fluid, particularly diesel fuels, gasolines, and kerosines.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see 6.3 – 6.5, Annex A1, and Annex A2.1.4 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 The present and growing international governmental requirements to add fatty acid methyl esters (FAME) to diesel fuel has had the unintended side-effect of leading to potential FAME contamination of jet turbine fuel in multifuel transport facilities such as cargo tankers and pipelines, and industry wide concerns.5.2 Analytical methods have been developed with the capability of measuring down to <5 mg/kg levels of FAME, however these are complex, and require specialized personnel and laboratory facilities. This Rapid Screening method has been developed for use in the supply chain by non specialized personnel to cover the range of 10 mg/kg to 150 mg/kg.1.1 This test method specifies a rapid screening method using flow analysis by Fourier transform infrared (FA-FTIR) spectroscopy with partial least squares (PLS-1) processing for the determination of the fatty acid methyl ester (FAME) content of aviation turbine fuel (AVTUR), in the range of 10 mg/kg to 150 mg/kg.NOTE 1: Specifications falling within the scope of this test method are: Specification D1655 and Defence Standard 91-91.NOTE 2: This test method detects all FAME components, with peak IR absorbance at approximately 1749 cm-1 and C8 to C22 molecules, as specified in standards such as Specification D6751 and EN 14214. The accuracy of the method is based on the molecular weight of C16 to C18 FAME species; the presence of other FAME species with different molecular weights could affect the accuracy.NOTE 3: Additives such as antistatic agents, antioxidants and corrosion inhibitors are measured with the FAME by the FTIR spectrometer. However the effects of these additives are removed by the flow analysis processing.NOTE 4: FAME concentrations from 150 mg/kg to 500 mg/kg, and below 10 mg/kg can be measured but the precision could be affected.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 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.1.4 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 This practice is intended to describe the data requirements necessary to support the review of new aviation turbine fuels or additives by ASTM members for the developers or sponsors of these new products.5.2 Its purpose is to guide the sponsor of a new fuel or new fuel additive through a defined evaluation process that includes the prerequisite testing and required periodic reviews with the subcommittee members. This practice provides a basis for calculating the volume of additive or fuel required for assessment, insight into the cost associated with taking a new fuel or new fuel additive through the evaluation process, and a defined path forward for introducing a new technology for the benefit of the aviation community.5.3 The allocation of resources necessary to support the full scope of the evaluation process is the responsibility of the sponsor of the new fuel or fuel additive. This will include laboratory, rig, or engine tests, if required, as well as support of OEM activities such as the Phase 1 and 2 reviews.5.4 This process may also be used to assess the impact of changes to fuels due to changes in production methods and/or changes during transportation. An example is the assessment of the impact of incidental materials on fuel properties. In the context of Practice D4054, incidental materials shall be considered as an additive.5.5 This guide is not an approval process. It is intended to describe test and analysis requirements necessary to generate data to support specification revision or development. This guide does not address the approval process for ASTM International standards.5.6 This guide does not purport to specify an all-inclusive listing of test and analysis requirements to achieve ASTM International issuance of a specification or specification revision. The final requirements will be dependent upon the specific formulation and performance of the candidate fuel or additive and be determined by the ASTM International task groups and committees charged with overseeing the specification development.5.7 Neither the generation of data and issuance of a research report described in this practice, nor the ultimate issuance of a new or revised ASTM fuel specification based on that data, constitutes approval to use the new or changed fuel or new additive on civil aircraft. As described in Appendix X2, the OEMs will conduct an internal review process in coordination with their aviation regulatory authorities to determine if the new fuel or additive is acceptable for use on each of their respective products. Only upon successful completion of this OEM internal review will the new fuel or additive be permitted for use on civil aircraft.5.8 This guide does not describe data requirements of other approving authorities, such as national aviation regulatory authorities, or of other organizations or industry associations. However, it is expected that the data generated in the conduct of the procedure will be used by the OEMs and national aviation regulatory authorities to support their internal approval processes (see Appendix X2) and may be useful for other purposes or other organizations.1.1 This standard practice provides procedures to develop data for use in research reports for new aviation turbine fuels, changes to existing aviation turbine fuels, or new aviation turbine fuel additives. These research reports are intended to support the development and issuance of new specifications or specification revisions for these products. This standard practice has also been used to evaluate the effect of incidental materials on jet fuel properties and performance.1.2 The procedures, tests, and selection of materials detailed in this practice are based on industry expertise to provide the necessary data to determine if the new or changed fuel or additive is suitable for use on existing aircraft and engines and for use in the current aviation operational and supply infrastructure. As such, it is primarily intended for the evaluation of drop-in fuels, but it can also be used for the evaluation of other fuels.1.3 Because of the diversity of aviation hardware and potential variation in fuel/additive formulations, not every aspect may be fully covered and further work may be required. Therefore, additional data beyond that described in this practice may be requested by the ASTM task force, Subcommittee J, or Committee D02 upon review of the specific composition, performance, or other characteristics of the candidate fuel or additive.1.4 Units of measure throughout this practice are stated in International System of Units (SI) unless the test method specifies non-SI units.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 This test method provides an indication of the presence of surfactants in aviation fuel. Like Test Methods D2550, D3602, D3948, and D7224, this test method can detect carryover traces of refinery treating residues in fuel as produced. In addition, these test methods can detect surface active substances added to or picked up by the fuel during handling from point of production to point of use. Certain additives can affect the WSI. Some of these substances affect the ability of filter separators to separate free water from the fuel.5.2 The small scale water separation tester has a measurement range from 0.0 WSI to 100.0 WSI.NOTE 1: WSI values greater than 100.0 WSI can be caused by a reduction in the light transmittance (see A1.1.5) of the test specimen due to material that was removed during the testing process.5.3 This test method was developed so refiners, fuel terminal operators, pipelines, and independent testing laboratory personnel can rapidly and precisely measure for the presence of surfactants, with a minimum of training, in a wide range of locations.1.1 This test method covers a procedure to rate the ability of aviation turbine fuels to release entrained and emulsified water when passed through a water-coalescing filter.1.2 Results are expressed as a Water Separation Index (WSI).1.3 The values stated in SI units are to be regarded as standard.1.3.1 Exception—Units in WSI are included.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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5.1 This test method will allow the determination of static dissipater additive in jet and middle distillate. These additives reduce the hazardous effects of static electricity generated by transfer and movement of jet and middle distillate fuels.1.1 This test method covers the determination of static dissipater additive (SDA) content of aviation turbine fuel and middle distillate fuels.1.2 The precision of this test method has been established for aviation turbine fuel over the concentration range of 1 mg/L to 12 mg/L. Higher concentrations can be determined by dilution, but the precision of the test method will not apply.NOTE 1: The SDA used to develop this test method was STADIS 4502 for aviation fuels and STADIS 450 and 4252 for middle distillates.1.3 The test method includes a procedure to concentrate the sulfonic acid component in the SDA prior to analysis.1.4 The test method only applies to SDAs that contain alkyl substituted sulfonic acid.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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.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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This specification covers precipitation hardened iron base superalloy forgings which are primarily intended for use as turbine rotor disks and wheels. Two heat treatments are covered and selection will depend upon design, service conditions, mechanical properties, and elevated temperature characteristics. The material shall be made by vacuum melting followed by consumable electrode vacuum arc or electroslag remelting. The forgings shall undergo the following tests: tension test, hardness test, stress rupture test, and creep test. Also, the forgings shall be subjected to non-destructive examinations like ultrasonic examination and liquid penetrant examination. The forgings shall be uniform in quality and condition, clean, sound, and free of cracks, seams, laps, shrinkage, and other injurious imperfections.1.1 This specification covers precipitation hardening iron base superalloy forgings which are primarily intended for use as turbine rotor disks and wheels.1.2 Two heat treatments are covered. Selection will depend upon design, service conditions, mechanical properties, and elevated temperature characteristics.1.3 All of the provisions of Specification A788/A788M, apply, except as amended herein.1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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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This specification covers reinforced plastic pipe and fitting system made from epoxy resin and glass-fiber reinforcement, together with adhesive for joint assembly, intended for services in aviation jet turbine fuel lines installed below ground. The fiberglass pipe shall be round and straight, and the pipe and fittings shall be of uniform density, resin content, and surface finish. Tests shall be conducted on the specimen to determine compliance with the following performance requirements: joint strength; hydrostatic strength; impact resistance; boil resistance; external load resistance; and degradation resistance.1.1 This specification covers a reinforced plastic pipe and fittings system made from epoxy resin and glass-fiber reinforcement, together with adhesive for joint assembly, intended for service up to 150°F (65.6°C) and 150-psig (1034-kPa) operating pressure and surges up to 275 psig (1896 kPa) in aviation jet turbine fuel lines installed below ground.1.2 The dimensionless designator NPS has been substituted in this specification for such traditional terms as nominal diameter, size, and nominal size.1.3 The values stated in inch-pound units are to be regarded as standard. The values in parentheses are for information only.1.4 The following safety hazards caveat pertains only to the test method portion, Section 9, of this specification: 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.NOTE 1: There is no known ISO equivalent to this standard.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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4.1 This test method simulates the environment encountered by fully formulated lubricating fluids in actual service and uses an accelerated oxidation rate to permit measurable results to be obtained in a reasonable time. The use of metals provides catalytic reactive surfaces of those materials commonly found in real systems. The high temperature and air agitation help accelerate the oxidation reactions that are expected to occur. Moisture in the air adds another realistic condition that encourages oil breakdown by facilitating acid formation.4.2 Interpretation of results should be done by comparison with data from oils of known field performance. The accelerated conditions likely will cause one or more of the following measurable effects: mass change and corroded appearance of some metals; change of viscosity; increase in acid number; measurable reaction products in the form of sludge; and mass loss of oil due to evaporation.4.3 This test method is most suitable for oils containing oxidation and corrosion inhibitors. Without such ingredient(s), the severe test conditions will yield rather drastic changes to the oil.1.1 This test method covers the testing of hydraulic oils, aircraft turbine engine lubricants, and other highly refined oils to determine their resistance to oxidation and corrosion degradation and their tendency to corrode various metals. Petroleum and synthetic fluids may be evaluated using moist or dry air with or without metal test specimens.1.2 This test method consists of a standard test procedure, an alternative Procedure 1, and an alternative Procedure 2. As there are variations possible with this test method, it will be up to the particular specification to establish the conditions required. In addition to temperature, the variables to specify if other than those of the standard procedure or alternative Procedure 1 or 2 are: test time, air flow and humidity, sample frequency, test fluid quantity, and metal specimen(s).1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3.1 Exception—The values in parentheses in some of the figures are provided for information only for those using old equipment based on non-SI units.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.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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5.1 Operating experience of gas turbines and diesel engines has shown that some of the ash-forming substances present in a fuel can lead to high temperature corrosion, ash deposition, and fuel system fouling. Ash-forming materials may be in a fuel as oil-soluble metallo-organic compounds as water-soluble salts or as solid foreign contamination. Their presence and concentration varies with the geographical source of a crude oil and they are concentrated in the residual fractions during the refining process. Although distillate fuel oils are typically contaminant free, ash-forming materials may be introduced later in the form of salt-bearing water or by contact with other petroleum products during transportation and storage. Specifications of gas turbine and diesel engine fuels and the significance of contamination and trace metals are detailed in Specifications D2880 and D975.5.1.1 Pre-conditioning of the fuel before it reaches the gas turbine or diesel engine has become a prerequisite for installations that use heavy petroleum fuel, and also for sites that use light distillate fuel oils. On-site fuel analysis to determine the extent of contamination is an integral part of a fuel quality management program. It is used first to determine the extent of the required treatment, and later, the effectiveness of the treatment. It starts with the delivery of the fuel, continues throughout fuel handling and ends only as the fuel is injected into the turbine or engine.5.1.2 Fuel contamination specifications vary among the different gas turbine manufacturers. However, without exception, each requires that contaminants must be as low as possible. In most power generation installations, it is the owner who has the responsibility of verifying fuel cleanliness in compliance with the turbine manufacturer's warranty specifications. This leads to an on-site analytical instrument performance requirement of below 1.0 mg/kg for several elements.1.1 This test method covers the determination of contaminants and materials as a result of corrosion in gas turbine or diesel engine fuels by rotating disc electrode atomic emission spectroscopy (RDE-AES).1.1.1 The test method is applicable to ASTM Grades 0-GT, 1-GT, 2-GT, 3-GT, and 4-GT gas turbine fuels and Grades Low Sulfur No. 1-D, Low Sulfur No. 2-D, No. 1-D, No. 2-D, and No. 4-D diesel fuel oils.1.1.1.1 Trace metal limits of fuel entering turbine combustor(s) are given as 0.5 mg/kg each for vanadium, sodium + potassium, calcium, and lead in Specification D2880 for all GT grades.1.1.2 This test method provides a rapid at-site determination of contamination and corrosive elements ranging from fractions of mg/kg to hundreds of mg/kg in gas turbine and diesel engine fuels so the fuel quality and level of required treatment can be determined.1.1.3 This test method uses oil-soluble metals for calibration and does not purport to quantitatively determine or detect insoluble particles.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. The preferred units for concentration are mg/kg (ppm by mass).1.3 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.1.4 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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