Metrologi och mätning. Fysikaliska fenomen
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ISO 19361:2017 applies to liquid scintillation counters and requires the preparation of a scintillation source obtained by mixing the test sample and a scintillation cocktail. The test sample can be liquid (aqueous or organic), or solid (particles or filter or planchet). ISO 19361:2017describes the conditions for measuring the activity of beta emitter radionuclides by liquid scintillation counting[14][15]. The choice of the test method using liquid scintillation counting involves the consideration of the potential presence of other beta emitter radionuclides in the test sample. In this case, a specific sample treatment by separation or extraction is implemented to isolate the radionuclide of interest in order to avoid any interference with other beta-, alpha- and gamma-emitting radionuclides during the counting phase. ISO 19361:2017 is applicable to all types of liquid samples having an activity concentration ranging from a few Bq·l−1 to 106 Bq·l−1. For a liquid test sample, it is possible to dilute liquid test samples in order to obtain a solution having an activity compatible with the measuring instrument. For solid samples, the activity of the prepared scintillation source shall be compatible with the measuring instrument. The measurement range is related to the test method used: nature of test portion, preparation of the scintillator - test portion mixture, measuring assembly as well as to the presence of the co-existing activities due to interfering radionuclides. Test portion preparations (such as distillation for 3H measurement, or benzene synthesis for 14C measurement, etc.) are outside the scope of this document and are described in specific test methods using liquid scintillation[2][3][4][5][6][7][8][9].
ISO 13347-4:2004 applies to industrial fans as defined in ISO 5801 and ISO 13349. It is limited to the determination of airborne sound emission for the specified set-ups. Vibration is not measured, nor is the sensitivity of airborne sound emission to vibration effects determined.
The sizes of the fan, which can be tested in accordance with ISO 13347-4:2004, are limited only by the practical aspects of the test installations.
ISO 13347-4:2004 determines sound power by using sound intensity measurements on a measurement surface which encloses the sound source. It provides guidelines on the acoustical environment, ambient noise, measurement surface, and number of measurements. The test set-ups are generally designed to represent the physical orientation of a fan installed in accordance with ISO 5801 and also used in ISO 13347-2.
1.1 This document specifies a direct measurement method for characterizing the surface roughness of the rail and wheel associated with rolling noise ("acoustic roughness"), in the form of a one-third octave band spectrum. This document describes a method for: a) selecting measuring positions along a track or selecting wheels of a vehicle; b) selecting lateral positions for measurements; c) the data acquisition procedure; d) measurement data processing in order to estimate a set of one-third octave band roughness spectra; e) presentation of this estimate for comparison with limits of acoustic roughness; f) comparison with a given upper limit in terms of a one-third octave band wavelength spectrum; g) the measuring system requirements. 1.2 It is applicable to the: a) compliance testing of reference track sections in relation to the acceptance test for noise emitted by railway vehicles; b) performance testing of track sections in relation to noise emitted by railway vehicles; c) acceptance of the running surface condition only in the case where the acoustic roughness is the acceptance criterion; d) assessment of the wheel surface condition as an input for the acoustic acceptance of brake blocks; e) assessment of the wheel and rail roughness as input to the calculation of combined wheel rail roughness; f) diagnosis of wheel-rail noise issues for specific tracks or wheels; g) assessment of the wheel and rail roughness as input to rolling noise modelling; h) assessment of the wheel and rail roughness as input to noise source separation methods. 1.3 It is not applicable to the: a) measurement of roughness (rail roughness, wheel roughness or combined roughness) using an indirect method; b) analysis of the effect of wheel-rail interaction, such as a “contact filter”; c) approval of rail and wheel reprofiling, including rail grinding operations, except for those where the acoustic roughness is specifically the approval criterion (and not the grinding quality criteria as provided in e.g. EN 13231-3); d) characterization of track and wheel geometry except where associated with noise generation.
This document specifies a test method for determination of the activity concentrations of the radionuclides potassium (K-40), uranium (U-238) and thorium (Th-232) in mineral-based construction products.
This document also specifies a method for the calculation of activity index (AI) according to Directive 2013/59/EURATOM, Annex 8 [12] for mineral-based construction products.
The method is intended to be used for factory production control.
This document specifies an engineering method for calculating the attenuation of sound during propagation outdoors in order to predict the levels of environmental noise at a distance from a variety of sources. The method predicts the equivalent continuous A-weighted sound pressure level (as described in ISO 1996-series) under meteorological conditions favourable to propagation from sources of known sound emission. These conditions are for downwind propagation or, equivalently, propagation under a well-developed moderate ground based temperature inversion, such as commonly occurs in clear, calm nights. Inversion conditions over extended water surfaces are not covered and may result in higher sound pressure levels than predicted from this document (see e.g. References [11] and [12]). The method also predicts a long-term average A weighted sound pressure level as specified in ISO 1996-1 and ISO 1996-2. The long-term average A weighted sound pressure level encompasses levels for a wide variety of meteorological conditions. Guidance has been provided to derive a meteorological correction based on the angular wind distribution relevant for the reference or long-term time interval as specified in ISO 1996-1:2016, 3.2.1 and 3.2.2. Examples for reference time intervals are day, night, or the hour of the night with the largest value of the sound pressure level. Long-term time intervals over which the sound of a series of reference time intervals is averaged or assessed representing a significant fraction of a year (e.g. 3 months, 6 months or 1 year). The method specified in this document consists specifically of octave band algorithms (with nominal mid-band frequencies from 63 Hz to 8 kHz) for calculating the attenuation of sound which originates from a point sound source, or an assembly of point sources. The source (or sources) may be moving or stationary. Specific terms are provided in the algorithms for the following physical effects: — geometrical divergence; — atmospheric absorption; — ground effect; — reflection from surfaces; — screening by obstacles. Additional information concerning propagation through foliage, industrial sites and housing is given in Annex A. The directivity of chimney-stacks to support the sound predictions for industrial sites has been included with Annex B. An example how the far-distance meteorological correction C0 can be determined from the local wind-climatology is given in Annex C. Experiences of the last decades how to predict the sound pressure levels caused by wind turbines is summarized in Annex D. The method is applicable in practice to a great variety of noise sources and environments. It is applicable, directly, or indirectly, to most situations concerning road or rail traffic, industrial noise sources, construction activities, and many other ground-based noise sources. It does not apply to sound from aircraft in flight, or to blast waves from mining, military, or similar operations. To apply the method of this document, several parameters need to be known with respect to the geometry of the source and of the environment, the ground surface characteristics, and the source strength in terms of octave band sound power levels for directions relevant to the propagation. If only A weighted sound power levels of the sources are known, the attenuation terms for 500 Hz may be used to estimate the resulting attenuation. The accuracy of the method and the limitations to its use in practice are described in Clause 9.