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5.1 The user-level calibration process may be used to verify that the DF tester is functioning properly, that it is within manufacturer specifications, and to perform minor adjustments to bring the unit back into conformance with manufacturer specifications.5.2 The DF tester user-level calibration described herein does not eliminate all error sources, nor does it guarantee the proper operation of the device. Several adjustments and repairs are beyond the scope of this standard, and manufacturer-approved calibrations are still recommended on an annual basis.1.1 This test method describes the equipment and procedure to ensure that the calibration performed by various dynamic friction tester (DF tester) users is uniform and in accordance with manufacturer specifications. There are three models of the DF tester in use: (1) USB/personal computer, (2) controller, and (3) X-Y plotter. Procedures specific to the different models are noted. User-level calibration software is separate from the operation software and must be obtained from the manufacturer for the USB/personal computer model.1.2 This test method is a static calibration of the vertical load, friction (µ) force, and speed of the DF tester. Compliance to this user-level calibration procedure ensures a higher level of repeatable and reproducible performance of the DF tester when used in accordance with Test Method E1911.1.3 The user-level calibration doesn’t include the replacement of the mu spring or the adjustment of linearity of the DF tester. It is recommended that DF testers be inspected by a manufacturer-approved laboratory on an annual basis to replace the mu spring, ensure linearity, and to identify other non user-serviceable wear.1.4 The values stated in SI (metric) units are to be regarded as standard. The inch-pound equivalents are rationalized, rather than exact mathematical conversions.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 DO may be either a corrosive or passivating agent in boiler/steam cycles and is therefore controlled to specific concentrations that are low relative to environmental and wastewater treatment samples. Out-of-specification DO concentrations may cause corrosion in boiler systems, which leads to corrosion fatigue and corrosion products — all detrimental to the life and efficient operation of a steam generator. The efficiency of DO removal from boiler feedwater by mechanical or chemical means, or both, may be monitored by continuously measuring the DO concentration before and after the removal process with on-line instrumentation. DO measurement is also a check for air leakage into the boiler water cycle.5.2 Feedwater chemistry guidelines for high-pressure boilers generally require specific feedwater DO concentrations: 5 μg/L or less for reducing all volatile treatment [AVT(R)]; 5–10 μg/L for oxidizing all volatile treatment [AVT(O)]; 50–200 μg/L for oxygenated treatment [OT] (3).5.3 In microelectronics production, DO can be detrimental in some manufacturing processes, for example, causing undesirable oxidation on silicon wafers.1.1 This test method covers the on-line determination of dissolved oxygen (DO) in water samples primarily in ranges from 0 to 500 μg/L (ppb), although higher ranges may be used for calibration. On-line instrumentation is used for continuous measurements of DO in samples that are brought through sample lines and conditioned from high-temperature and high-pressure sources when necessary.1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered 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. For specific hazards statements, see 6.5.1.4 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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Information technology - Coding of audio-visual objects - Part 5: Reference software AMENDMENT 3: Visual new level and tools

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4.1 The test results enable the comparison of A-weighted sound emission from vacuum cleaners, backpack vacuum cleaners, extractors, or hard-floor cleaning machines when tested under the condition of this test method.1.1 This test method calculates the overall A-weighted sound power level emitted by small portable upright, canister, combination vacuum cleaners, backpack vacuum cleaners, hard-floor cleaning machines, extractors, and central vacuum cleaner motorized nozzles intended for operation in domestic and commercial applications.1.1.1 To determine the Sound Power Level of a central vacuum at the power unit location refer to Test Method F2544.1.2 A-weighted sound pressure measurements are performed on a stationary vacuum cleaner, extractor, hard-floor cleaning machine, or backpack vacuum cleaner in a semi-reverberant room. This test method determines sound power by a comparison method for small noise sources, that is, comparison to a broadband reference sound source.1.3 This test method describes a procedure for determining the approximate A-weighted sound power level of small noise sources. This test method uses a non-special semi-reverberant room.1.4 Results are expressed as A-weighted sound power level in decibels (referenced to one picowatt).1.5 The values stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only.NOTE 1: The F11.21 subcommittee is actively pursuing new market relevant carpets with the assistance of the carpet industry. Although plush and Freize carpet panels are no longer available for purchase, some laboratories may still have samples for testing. In such cases, the table values remain valid.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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4.1 This practice permits an analyst to compare the general performance of an instrument on any given day with the prior performance of an instrument. This practice is not necessarily meant for comparison of different instruments with each other even if the instruments are of the same type and model. This practice is not meant for comparison of the performance of one instrument operated under differing conditions.1.1 This practice describes two levels of tests to measure the performance of laboratory Fourier transform mid-infrared (FT-MIR) spectrometers equipped with a standard sample holder used for transmission measurements.1.2 This practice is not directly applicable to Fourier transform infrared (FT-IR) spectrometers equipped with various specialized sampling accessories such as flow cells or reflectance optics, nor to Fourier transform near-infrared (FT-NIR) spectrometers, nor to FT-IR spectrometers run in step scan mode.1.2.1 If the specialized sampling accessory can be removed and replaced with a standard transmission sample holder, then this practice can be used. However, the user should recognize that the performance measured may not reflect that which is achieved when the specialized accessory is in use.1.2.2 If the specialized sampling accessory cannot be removed, then it may be possible to employ a modified version of this practice to measure spectrometer performance. The user is referred to Guide E1866 for a discussion of how these tests may be modified.1.2.3 Spectrometer performance tests for FT-NIR spectrometers are described in Practice E1944.1.2.4 Performance tests for dispersive MIR instruments are described in Practice E932.1.2.5 For FT-IR spectrometers run in a step scan mode, variations on this practice and information provided by the instrument vendor should be used.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—Informational inch-pound units are provided in 5.4.1.4 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 The function and operation of equipment in the field often preclude the measurement of the free-field sound pressure levels of a single piece of equipment in the absence of interfering sound from other equipment operating at the same time. The two-surface method will provide, in most cases, a reliable estimate of the normal sound power levels of a specimen operating in an adverse environment.5.2 This test method is intended for use in the field in the presence of what is normally regarded as interfering background noise. This test method is based upon the work of Hubner 5,6 and Diehl,7 but differs from all other current sound power measurement procedures by requiring simultaneous measurement at both conformal surfaces and by resolving time-averaged sound pressure levels at both surfaces to within 0.1 dB. These two features, simultaneous recording and 0.1dB resolution, enable source sound power to be calculated when the direct sound field of the source is actually lower in level than the ambient noise.5.3 The use of this test method is expected to be primarily for the relative assessment of the sound power from similar sources or for the prediction of sound levels in a plant based upon measurements of similar sources in another plant. This test method is believed to be capable of yielding a reasonably good estimate of absolute power level with proper care of application and full conformance to the provisions of this procedure.5.4 The two-surface method is applicable only when the two measurement surfaces can be physically selected to produce positive values of the difference in average sound pressure level. That is, the inner surface sound pressure level minus the outer surface sound pressure level must be at least +0.1 dB. This limitation applies to each frequency band and each constituent surface area investigated. Only the frequency band in which a zero or negative difference occurs is it considered invalid and usually adjacent bands will be valid. In practice, only rarely will all three one-third octave bands of a given octave yield invalid data at all constituent areas. Therefore, less than complete results are permissible when one-third octave analysis is used and full octave results are reported.5.5 The two-surface method may not produce results when testing some very large machines in very reverberant rooms or in rooms having a volume less than about 20 times the space enclosed by an envelope around the larger dimensions of the machine. In such cases, the sound pressure level close to the machine may not decrease in any regular way with increasing distance from a machine surface, making it impossible to select two measurement surfaces producing positive differences of sound pressure level.1.1 This test method covers the field, or in situ measurement of sound power level by the two-surface method. The test method is designed to minimize the effects of reverberant conditions, directivity of the noise source under consideration, and the effects of ambient noise from other nearby equipment operating at the same time.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 and health practices and determine the applicability of regulatory limitations prior to use.

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