Metrologi och mätning. Fysikaliska fenomen

Kommittébeteckning: SIS/TK 119 (Svetsutrustning)
Källa: CEN
Svarsdatum: den 22 okt 2017
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This International Standard specifies requirements for Bourdon-tube pressure gauges normally used with compressed gas systems at pressures up to 30 MPa (300 bar) in welding, cutting and allied processes. It also covers use for dissolved acetylene and for liquefied gases under pressure.

It does not cover gauges for acetylene in acetylene-manufacturing plants.

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: ISO
Svarsdatum: den 31 okt 2017
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This part of ISO 17201 specifies a method to determine the acoustic source energy of the muzzle blast for calibres of less than 20 mm or explosive charges of less than 50 g TNT equivalent. It is applicable at distances where peak pressures less than 1 kPa (equivalent to a peak sound pressure level of 154 dB) are observed. The source energy, directivity of the source and their spectral structure determined by this procedure can be used as input data to sound propagation programmes, enabling prediction of shooting noise in the neighbourhood of shooting ranges. Additionally, the data can be used to compare sound emission from different types of guns or different types of ammunition used with the same gun.

This part of ISO 17201 is applicable to guns used in civil shooting ranges but it can also be applied to military guns. It is not applicable to the assessment of hearing damage or sound levels in the non-linear region.

Kommittébeteckning: SIS/TK 170 (Luftbehandlingsteknik)
Källa: CEN
Svarsdatum: den 6 nov 2017
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This European Standard is one of a series of European Standards dedicated to air-cooled heat exchangers.

— forced convection air cooled refrigerant condensers as specified in EN 327;

— forced convection unit air coolers for refrigeration as specified in EN 328;

— air cooled liquid coolers "dry coolers" as specified in EN 1048.

This standard provides information for assessing and presenting the acoustic emission characteristics of heat exchangers under stationary operating conditions.

This European Standard is applicable to selfstanding forced convection air cooled refrigerant condensers and air cooled liquid coolers "dry coolers" and air coolers.

Kommittébeteckning: SIS/TK 254 (Järnvägar)
Källa: CEN
Svarsdatum: den 23 nov 2017
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1.1 This European Standard specifies a direct 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 standard 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) performance 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.

d) characterization of track and wheel geometry except where associated with noise generation.

Ämnesområden: Mätinstrument
Kommittébeteckning: SIS/TK 507 (Tekniska produktspecifikationer (TPS))
Källa: CEN
Svarsdatum: den 24 nov 2017
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This document provides the most important design and metrological characteristics of callipers

- with analogue indication: verniere scale or circular scale (dial), and

- with digital indication: digital display

Kommittébeteckning: SIS/TK 110 (Akustik och buller)
Källa: ISO
Svarsdatum: den 11 dec 2017
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This document specifies procedures for measuring and reporting the noise emission of information technology and telecommunications equipment.

NOTE 1 This document is considered part of a noise test code (see 3.1.2) for this type of equipment, and is based on basic noise emission standards (see 3.1.1) ISO 3741, ISO 3744, ISO 3745, ISO 9295 and ISO 11201.

The basic emission quantity is the A-weighted sound power level which may be used for comparing equipment of the same type but from different manufacturers, or for comparing different equipment.

Three basic noise emission standards for determination of the sound power levels are specified in this document in order to avoid undue restriction on existing facilities and experience. ISO 3741 specifies comparison measurements in a reverberation test room; ISO 3744 and ISO 3745 specify measurements in an essentially free field over a reflecting plane. Any one of these three basic noise emission standards can be selected and used exclusively in accordance with this document when determining sound power levels of a machine.

The A-weighted sound power level is supplemented by the A-weighted emission sound pressure level determined at the operator position(s) or the bystander positions, based on basic noise emission standard ISO 11201. This sound pressure level is not a worker's immission rating level, but it can assist in identifying any potential problems that could cause annoyance, activity interference, or hearing damage to operators and bystanders.

Methods for determination of whether the noise emission includes prominent discrete tones or is impulsive in character are specified in Annexes D and E, respectively.

This document is suitable for type tests and provides methods for manufacturers and testing laboratories to obtain comparable results.

The methods specified in this document allow the determination of noise emission levels for a functional unit (see 3.1.4) tested individually.

The procedures apply to equipment which emits broad-band noise, narrow-band noise and noise which contains discrete-frequency components, or impulsive noise.

The sound power and emission sound pressure levels obtained can serve noise emission declaration and comparison purposes (see ISO 9296).

NOTE 2 The sound power levels and emission sound pressure levels obtained are not to be considered as installation noise immission levels; however, they can be used for installation planning (see ECMA TR/27[5]).

If sound power levels obtained are determined for a number of functional units of the same production series, they can be used to determine a statistical value for that production series (see ISO 9296).

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This International Standard specifies how screens, furniture and single objects intended for interior use will be assessed with regard to sound absorption. The International Standard also specifies the evaluation of sound attenuation for floor screens. It also specifies under which circumstances various interior products for offices, schools and other public spaces are considered as plane absorbers or as discrete single objects. A product considered as a single object and intended for interior use, is measured according to ISO 354, and evaluated by its equivalent sound absorption area or object sound absorption coefficient in octave bands. This International Standard defines interior products and single objects and it comprises additional information regarding measurements and assessment of single objects.

The sound absorption as specified in this International Standard can be used a) to calculate reverberation time characteristics in rooms;

b) to calculate room acoustic parameters using ray tracing software.