Metrologi och mätning. Fysikaliska fenomen

Ämnesområden: Färg- och ljusmätning
Kommittébeteckning: SIS/TK 380 (Ergonomi)
Källa: CEN
Svarsdatum: den 2 apr 2019
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This document specifies colour-matching functions for use in colorimetry. Two sets of colour-matching functions are specified.

a) Colour-matching functions for the CIE 1931 standard colorimetric observer.

This set of colour-matching functions is representative of the colour-matching properties of observers with normal colour vision for visual field sizes of angular subtense from about 1° to about 4°, for vision at photopic levels of adaptation.

b) Colour-matching functions for the CIE 1964 standard colorimetric observer.

This set of colour-matching functions is representative of the colour-matching properties of observers with normal colour vision for visual field sizes of angular subtense greater than about 4°, for vision at sufficiently high photopic levels and with spectral power distributions such that no participation of the rod receptors of the retina is to be expected.

Ämnesområden: Färg- och ljusmätning
Kommittébeteckning: SIS/TK 380 (Ergonomi)
Källa: CEN
Svarsdatum: den 2 apr 2019
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This document specifies methods of calculating the tristimulus values of colour stimuli for which the spectral distributions are provided. These colour stimuli can be produced by self-luminous light sources or by reflecting or transmitting objects.

This document requires that the colour stimulus function be tabulated at measurement intervals of 5 nm or less in a wavelength range of at least 380 nm to 780 nm. Extrapolation methods are suggested for cases where the measured wavelength range is less than 380 nm to 780 nm.

The standard method is defined as summation at 1 nm intervals over the wavelength range from 360 nm to 830 nm. Alternative abridged methods are defined for larger intervals (up to 5 nm) and shorter ranges (down to 380 nm to 780 nm). The alternative methods are to be used only when appropriate and when the user has reviewed the impact on the final results.

This document can be used in conjunction with the CIE 1931 standard colorimetric observer or the CIE 1964 standard colorimetric observer.

Kommittébeteckning: SIS/TK 424 (Kemiska vattenundersökningar)
Källa: CEN
Svarsdatum: den 8 apr 2019
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This document specifies a test method for the determination of gross beta activity concentration in non-saline waters. The method covers non-volatile radionuclides with maximum beta energies of approximately 0,3 MeV or higher. Measurement of low energy beta emitters (e.g. 3H, 228Ra, 210Pb, 14C, 35S and 241Pu) and some gaseous or volatile radionuclides (e.g. radon and radioiodine) might not be included in the gross beta quantification using the test method described in this document.

This test method is applicable to the analysis of raw and drinking waters. The range of application depends on the amount of total soluble salts in the water and on the performance characteristics (background count rate and counting efficiency) of the counter used.

It is the laboratory’s responsibility to ensure the suitability of this method for the water samples tested.

Kommittébeteckning: SIS/TK 424 (Kemiska vattenundersökningar)
Källa: CEN
Svarsdatum: den 11 apr 2019
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This document specifies a method for the measurement of 210Po in all types of waters by alpha spectrometry.

The method is applicable to test samples of supply/drinking water, rainwater, surface and ground water, marine water, as well as cooling water, industrial water, domestic, and industrial wastewater after proper sampling and handling, and test sample preparation. A filtration of the test sample is necessary.

The detection limit depends on the sample volume, the instrument used, the background count rate, the detection efficiency and the chemical yield. The method described in this document, using currently available alpha spectrometry apparatus, has a detection limit of approximately 5 mBq.l-1, which is lower than the WHO criteria for safe consumption of drinking water (100 mBq·l-1). This value can be achieved with a counting time of 24 hours for a sample volume of 500 ml.

The method described in this document is applicable in the event of an emergency situation.

The analysis of 210Po adsorbed to suspended matter is not covered by this method.

It is the user’s responsibility to ensure the validity of this test method for the water samples tested.

If suspended material has to be removed or analysed, filtration at 0,45 μm is recommended. The analysis of the insoluble fraction requires a mineralization step that is not covered by this document (see NF M 60-790-4[13]). In this case, the measurement is made on the different phases obtained. The final activity is the sum of all the measured activity concentrations.

Ämnesområden: Färg- och ljusmätning
Kommittébeteckning: SIS/TK 380 (Ergonomi)
Källa: CEN
Svarsdatum: den 16 apr 2019
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This document specifies a method of calculating the coordinates of the CIE 1976 L*a*b* colour space, including correlates of lightness, chroma and hue. It includes two methods for calculating Euclidean distances in this space to represent the perceived magnitude of colour differences.

This document is applicable to tristimulus values calculated using colour-matching functions of the CIE 1931 standard colorimetric system or the CIE 1964 standard colorimetric system. This document can be used for the specification of colour stimuli perceived as belonging to a reflecting or transmitting object, where a three-dimensional space more uniform than tristimulus space is required.

This document does not apply to colour stimuli perceived as belonging to an area that appears to be emitting light as a primary light source, or that appears to be specularly reflecting such light.

This document is applicable to self-luminous displays, such as cathode ray tubes, if they are being used to simulate reflecting or transmitting objects and if the stimuli are appropriately normalized.

Calculating the reverse transformation is shown in Annex A.

Kommittébeteckning: SIS/TK 197 (Byggakustik)
Källa: CEN
Svarsdatum: den 20 maj 2019
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This part of ISO 12999 specifies procedures for assessing the measurement uncertainty of sound insulation in building acoustics. It provides for

— a detailed uncertainty assessment;

— a determination of uncertainties by inter-laboratory tests;

— an application of uncertainties.

Furthermore, typical uncertainties are given for quantities determined according to ISO 10140, ISO 16283 and ISO 717 (all parts).