“JJG 52-1999”的系列
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  • 废止 ANSI C52.1-2000Motor & Generators
    发布日期:
    2000-01
    来源:
    新信标准
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    废止 ANSI C52.1-2000 Motor & Generators
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    适用范围:There is no abstract currently available for this document
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    废止 ISA RP52.1-1975 RECOMMENDED ENVIRONMENTS FOR STANDARDS LABORATORIES
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    适用范围:There is no abstract currently available for this document
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    废止 ASHRAE STD 52.1-1992(R2007) GRAVIMETRIC AND DUST-SPOT PROCEDURES FOR TESTING AIR-CLEANING DEVICES USED IN GENERAL VENTILATION FOR REMOVING PARTICULATE MATTER
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    适用范围:There is no abstract currently available for this document
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  • 有效 ISA TR52.00.01-2006Recommended Environments for Standards Laboratories
    发布日期:
    2006-12-29
    语言:
    英文
    来源:
    新信标准
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    有效 ISA TR52.00.01-2006 Recommended Environments for Standards Laboratories
    语言:英文
    适用范围:The usual concept that working standards are less accurate thanreference standards and that the environmental requirements areless demanding is the basis for this technical report. The sameconcept carries over, in general, in differentiating between Type Iand Type II laboratories. It should be emphasized that thistechnical report is intended to apply to Echelon II laboratoriesonly (see Clause 3). Moreover, this technical report servesprimarily as a guideline to the design, construction, and operationof standards laboratories and, thus, is not to be construed asmandatory requirements. In many cases satisfactory repeatability ofcalibrations can be obtained even though the environment does notcomply fully with this technical report. For additional information, see ISAO/R 554, StandardAtmospheres, NCSL RP-7, Laboratory Design, and NCSLRP-14, Guide to Selecting Standards-LaboratoryEnvironments. Purpose The measured value assigned to a standard or measurementinstrument has the essential qualification that the assigned valuewas valid at the specific time and under the specific conditions ofthe calibration. No assurance is made regarding the future value orthe value under different conditions. If the device is physicallystable with time, and if a sufficient history is compiled underenvironmental conditions that are compatible with the previouscalibration, the confidence level of the assigned value increases.If the specific conditions of measurements are not repeated whenthe device is again calibrated, any variables introduced can createsubstantial uncertainty. With this fact in mind, it is obvious thatthere is a need for knowing and maintaining the environmentalfactors associated with the various types of measurement standardsand instruments. Aside from the necessity of securing repeatablemeasurements, environmental controls help to reduce the number oftedious corrections necessary in making measurements that areaffected by adverse environments.
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    有效 ASHRAE STD 52.2-2017 Method of Testing General Ventilation Air-Cleaning Devices for Removal Efficiency by Particle Size
    语言:英文
    适用范围:This standard describes a method of laboratory testing to measure the performance of general ventilation air-cleaning devices. The method of testing measures the performance of aircleaning devices in removing particles of specific diameters as the devices become loaded by standardized loading dust fed at intervals to simulate accumulation of particles during service life. The standard defines procedures for generating the aerosols required for conducting the test. The standard also provides a method for counting airborne particles of 0.30 to 10 μm in diameter upstream and downstream of the air-cleaning device in order to calculate removal efficiency by particle size. This standard also establishes performance specifications for the equipment required to conduct the tests, defines methods of calculating and reporting the results obtained from the test data, and establishes a minimum efficiency reporting system that can be applied to air-cleaning devices covered by this standard. PURPOSE This standard establishes a test procedure for evaluating the performance of air-cleaning devices as a function of particle size.
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