Metrologi och mätning. Fysikaliska fenomen

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: ISO
Svarsdatum: den 6 feb 2023
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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 Parts 1 to 2 of ISO 1996) 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[5]. and[6]).
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 3.2.1 and 3.2.2 of ISO 1996-1:2016. 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. Experience of the last decade 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. lt 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.
lf 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.

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: ISO
Svarsdatum: den 16 feb 2023
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This document defines the acoustic performance of four classes (Classes A, B, C and D) of pipe insulation.
It also defines a standardized test method for measuring the acoustic performance of any type of material system construction, thereby allowing existing and new insulation constructions to be rated against the four classes. Furthermore, this document presents some typical types of construction that would be expected to meet these acoustic performance classes.
This document is applicable to the acoustic insulation of cylindrical steel pipes and to their piping components. It is valid for pipes up to 1 m in diameter and a minimum wall thickness of 4,2 mm for diameters below 300 mm, and 6,3 mm for diameters from 300 mm and above. It is not applicable to the acoustic insulation of rectangular ducting and vessels or machinery.
This document covers both design and installation aspects of acoustic insulation and provides guidance to assist noise control engineers in determining the required class and extent of insulation needed for
a particular application. It gives typical examples of construction methods, but the examples are for information only and not meant to be prescriptive.
This document emphasises the aspects of acoustic insulation that are different from those of thermal insulation, serving to guide both the installer and the noise control engineer. Details of thermal insulation are beyond the scope of this document.

Kommittébeteckning: SIS/TK 116 (Oorganiska ytbeläggningar)
Källa: CEN
Svarsdatum: den 20 feb 2023
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This document reviews methods for measuring the thickness of metallic and other inorganic coatings on both metallic and non-metallic substrates (see Tables 1, 2 and 3). It is limited to tests already specified, or to be specified, in International Standards, and excludes certain tests that are used for special applications.

Kommittébeteckning: SIS/TK 254 (Järnväg, tunnelbana och spårväg)
Källa: CEN
Svarsdatum: den 23 feb 2023
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This document addresses the measurement of source terms for environmental noise calculation for rail traffic (including light rail, such as trams, metros, etc). It is applicable to the measurement of in-service trains on operational tracks.
It is not applicable to type acceptance testing of rolling-stock or tracks, or to derive source terms for time domain models.
The following rail traffic noise source types are in the scope:
• Rolling noise ;
• Traction noise ;
• Aerodynamic noise ;
• Impact noise (e.g. rail joints, switch and crossings, wheel flats) ;
• Braking noise ;
• Bridge noise ;
• Squeal noise.
Noise from rail vehicles at standstill, such as stationary engine idling and auxiliary equipment at yards and stations is covered by EN ISO 3095:2013 for measurement procedures and operating conditions, and by ISO 3740:2019, and ISO 3744:2010 for the determination of sound power.
The calculation of the propagation of sound is part of generally standardized propagation models which are not addressed in this document.
Noise from fixed installations (e.g.: stations, depots, electricity sub-stations) are not in the scope of this document.
Source terms are specific to a vehicle and track type. The scope includes measurement procedures and conditions and sampling requirements.

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: ISO
Svarsdatum: den 6 mar 2023
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This document specifies methods for measuring the airborne noise emitted by small air-moving devices (AMDs), such as those used for cooling electronic, electrical, and mechanical equipment where the sound power level of the AMD is of interest.
Examples of these AMDs include propeller fans, tube-axial fans, vane-axial fans, centrifugal fans, motorized impellers, and their variations.
This document describes the test apparatus and methods for determining the airborne noise emitted by small AMDs as a function of the volume flow rate and the fan static pressure developed by the AMD on the test apparatus. It is intended for use by AMD manufacturers, by manufacturers who use AMDs for cooling electronic equipment and similar applications, and by testing laboratories. It provides a method for AMD manufacturers, equipment manufacturers and testing laboratories to obtain comparable results. Results of measurements made in accordance with this document are expected to be used for engineering information and performance verification, and the methods can be cited in purchase specifications and contracts between buyers and sellers. The ultimate purpose of the measurements is to provide data to assist the designers of electronic, electrical or mechanical equipment which contains one or more AMDs.
Based on experimental data, a method is given for calculating the maximum volume flow rate of the scaled plenum up to which this document is applicable.

Kommittébeteckning: SIS/TK 433 (Färg och lack)
Källa: CEN
Svarsdatum: den 8 mar 2023
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This document specifies a formalism for the calculation of the illuminant metamerism of solid surface colours. It cannot be applied to colours of effect coatings without metrical adaptation.
This document only covers the phenomenon of metamerism for change of illuminant, which has the greatest meaning in practical application. In the case of chromaticity coordinates of a pair of samples under reference conditions that do not exactly match, recommendations are given on which correction measures are to be taken. Regarding the reproduction of colours, the metamerism index is used as a measure of quality in order to specify tolerances for colour differences between a colour sample and a colour match under different illumination conditions.
The quantification of the illuminant metamerism of pairs of samples is formally performed by a colour
difference assessment, for which tolerances that are common for the evaluation of residual colour differences can be used.
NOTE In the colorimetric literature and textbooks, the term geometric metamerism is sometimes used for the case that two colours appear to be the same under a specific geometry for visual assessment and selected
standard observer and standard illuminant pair, but is perceived as two different colours at changed observation geometry. The term geometric metamerism is different to metamerism described in this document.

Kommittébeteckning: SIS/TK 507 (Tekniska produktspecifikationer (TPS))
Källa: CEN
Svarsdatum: den 15 mar 2023
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This document develops the terminology and concepts for profile morphological segmentation. In particular it describes the watershed segmentation method, the Wolf pruning method and the Crossingthe- Line Method. This document assumes a continuous surface.

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: CEN
Svarsdatum: den 16 mar 2023
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This document specifies methods for determining the sound power level of a noise source from sound pressure levels measured on a surface enveloping the noise source (machinery or equipment) in an environment that approximates to an acoustic free field near one or more reflecting planes. The sound power level produced by the noise source, in frequency bands or with A-weighting applied, is calculated using those measurements.
NOTE Differently shaped measurement surfaces can yield differing estimates of the sound power level of a given noise source which are accounted for in the uncertainty associated with this test method, or a noise
test code that refers to this method. An appropriately drafted noise test code (see ISO 12001) gives detailed information on the selection of the surface.

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: CEN
Svarsdatum: den 16 mar 2023
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This document gives guidance on the determination of (measurement) uncertainties of sound power levels determined according to ISO 3741, ISO 3743-1, ISO 3743-2, ISO 3744, ISO 3745, ISO 3746 and ISO 3747.

Kommittébeteckning: SIS/TK 619 (Obemannade Luftfartyg och UAS)
Källa: ISO
Svarsdatum: den 29 mar 2023
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This document specifies the test conditions and methods to be used for the vibration testing of unmanned aircraft system (UAS, including unmanned aircraft and ground station) which applies to level II through V according to ISO 21895.
The vibration techniques and values specified are intended to reflect the vibration environment that the UAS will be exposed to during transportation and flight.