The basis of the mandate of the World Radiation Center (WRC) – to provide homogeneity of global solar radiation measurements – is the agreement between MeteoSwiss and the “Schweizerisches Forschungsinstitut für Hochgebirgsklima und Medizin” Foundation. This regulation also contains the recommendation of the WMO-CIMO VII (1977) relating to the tasks of the WRC.
A pre-requisite is the participation of Switzerland in the Comité International des Poids et Mesures Mutual Recognition Arrangement (CIPM-MRA). The Federal Institute of Metrology (METAS) lists the PMOD/WRC as a “Designated Institute”. The MRA was signed on 14 October 1999 by METAS.
In addition, the World Meteorological Organisation (WMO) as an international organisation, signed the CIPM-MRA on 1 April 2010. As a result, the PMOD/WRC was further integrated into the European Association of National Metrology Institutes and Bureau International des Poids et Mesures (EURAMET, BIPM). The PMOD/WRC also acts as a “Designated Institute” within the WMO (Figure 1).
The declaration of various measurement units, the so-called Calibration and Measurement Capabilities (CMCs), were applied at the BIPM after examination by technical committees of EURAMET. The BIPM lists the Key Comparison Database (KCDB) in which all valid CMCs of the CIPM MRA countries are listed.
With our Quality Management System (QMS) at the PMOD/WRC, we meet the ISO/IEC 17025 international standard for parts of the calibration activities of our World Radiation Center (Figure 2). The QMS certification for this standard is in principle based on self-declaration.
Download the self-declaration →
The basis for the international recognition of the PMOD/WRC calibration activities, however, is the approval by the Technical Committee for Quality (TC-Q) of EURAMET, which checks the PMOD/WRC QMS to the requirements of the ISO/IEC 17025 standard and monitors the system regularly. ISO/IEC 17025 (“General requirements for the competence of testing and calibration laboratories”) is a common accreditation standard which testing and calibration laboratories hold to be deemed technically competent.
Figure 1. Involvement of Metrology and Meteorology at PMOD/WRC. Click image to enlarge.
Figure 2. The Quality Management System (QMS) at PMOD/WRC. The WRC SRS, WCC-UV and IRS sections (light blue shading), perform calibrations according to ISO/IEC 17025. Click image to enlarge.
After acceptance of 2 additional CMCs in 2020, PMOD/WRC now has 8 different CMCs which are listed in the BIPM KCDB. These include the following which are detailed in Table 1:
• Responsivity, solar irradiance pyranometer (1)
• Responsivity, solar irradiance pyrheliometer (1)
• Responsivity, solar irradiance broadband detector (4)
• Responsivity, solar spectral irradiance solar spectroradiometer (2)
Table 1. CMCs of PMOD/WRC. The table can be downloaded from the BIPM KCDB webpage using the keyword, “PMOD/WRC”, in the search field.
|
Approval Date |
Quantity |
Instrument or Artifact |
Measurement Method |
Parameters |
Min – Max Range |
Unit |
Expanded Uncertainty |
Comments |
|
2018-11-28 |
Responsivity, solar, irrad. |
Broadband detector |
Radiometer to spectro-radiometer comparison |
Global solar UV irrad., UV index: 0.1 – 10; Type of source : Sun and clear or cloudy sky; Angle between normal of receiver surface and solar beam : 23° – 50°; Inclination : horizontal; Total column ozone (atmospheric): 2 – 5 mm STP (200 – 500 DU) |
1.0E-4 – 40.0 |
V/(Wm-2) |
3.1 |
Weighting: Erythema CIE Wavelength range: 280 – 400 nm |
|
2018-11-28 |
Responsivity, solar, irrad. |
Broadband detector |
Radiometer to spectro-radiometer comparison |
Global solar UVB irrad.: 0.1 – 1.5 Wm-2; Type of source: Sun and clear or cloudy sky; Angle between normal of receiver surface and solar beam: 23° – 50°; Inclination: horizontal; Total column ozone (atmospheric) : 2 – 5 mm STP (200 – 500 DU) |
1.0E-4 – 2.0 |
V/(Wm-2) |
3.0 |
Weighting: uniform, 280 – 315 nm Wavelength range: 280 – 315 nm |
|
2018-11-28 |
Responsivity, solar, irrad. |
Broadband detector |
Radiometer to spectro-radiometer comparison |
Global solar UVA irrad.: 0.1 – 50 Wm-2; Type of source: Sun and clear or cloudy sky; Angle between normal of receiver surface and solar beam: 23° – 50°; Inclination: horizontal; Total column ozone (atmospheric): 2 – 5 mm STP (200 – 500 DU) |
1.0E-4 – 0.1 |
V/(Wm-2) |
3.0 |
Weighting: uniform, 315 – 400 nm Wavelength range: 315 – 400 nm |
|
2018-11-28 |
Responsivity, solar, irrad. |
Broadband detector |
Radiometer to spectro-radiometer comparison |
Global solar UV irrad.: 0.1 – 50 Wm-2; Type of source: Sun and clear or cloudy sky; Angle between normal of receiver surface and solar beam: 23° – 50°; Inclination: horizontal; Total column ozone (atmospheric): 2 – 5 mm STP (200 – 500 DU) |
1.0E-4 – 0.1 |
V/(Wm-2) |
3.5 |
Weighting: uniform, 280 – 400 nm Wavelength range: 280 – 400 nm |
|
2019-05-03 |
Responsivity, solar, spectral, irrad. |
Solar spectro-radiometer |
Spectro-radiometer to spectro-radiometer comparison |
Wavelength range: 300 – 310 nm; Bandwidth: 0.2 – 10 nm; Spectral irrad.: 0.0001 -0.7 (W/m2)/nm |
A/(Wm-2 nm-1), V/(Wm-2 nm-1), reading/(Wm-2 nm-1) |
7.34 |
||
|
2019-05-03 |
Responsivity, solar, spectral, irrad. |
Solar spectro-radiometer |
Spectro-radiometer to spectro-radiometer comparison |
Wavelength: 310 – 500 nm; Bandwidth: 0.2 – 10 nm; Spectral irrad.: 0.0001 – 2.5 (W/m2)/nm |
A/(Wm-2 nm-1), V/(Wm-2 nm-1), reading/(Wm-2 nm-1) |
1.74 |
||
|
2020-02-07 |
Responsivity, solar, irrad. |
Pyrheliometer |
Pyrheliometer comparison |
Mean direct solar irrad.: 800 – 1000 Wm-2; Type of source: Sun and clear sky; Reference system: World Radiometric Ref. (WRR); Amb. T: -15 – +30 °C |
W/(m2V2), µV/(Wm-2), 1/m2, 1/(Wm-2) |
0.12 |
Ambient air T: 5 – 30 °C. Uncertainty for deviation of WRR wrt SI <0.3%. |
|
|
2020-02-07 |
Responsivity, solar, irrad. |
Pyranometer |
Pyranometer comparison |
Inclination: 0.0°; Angle between normal of receiver surface and solar beam: 24° – 50°; Mean global solar irrad.: 800 – 1000 Wm-2; Ref. system: World Radiometric Ref. (WRR); Type source: Sun & clear sky |
µV/(Wm-2) |
0.66 |
Uncertainty for deviation of WRR with respect to SI <0.3%. |