Speciality Gases Practice 4. Our quality, your safety. Accredited Test and Calibration Laboratory Speciality Gases Centre in Hörstel.

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1 Speciality Gases Practice 4 Our quality, your safety. Accredited Test and Calibration Laboratory Speciality Gases Centre in Hörstel.

2 Accredited Westfalen quality. Speciality Gases Centre in Hörstel. They have long been compulsory for measurements in many sectors, and are fast becoming so in more: gas mixtures with compositions determined by accredited procedures. The Westfalen Speciality Gases Centre, located in the Westphalian town of Hörstel (near Osnabrück) has been accredited as a test laboratory since In the same year the centre also gained accreditation from the German Calibration Service (DKD - Deutscher Kalibrierdienst) as a calibration laboratory. The Speciality Gases Centre therefore fulfils the General Requirements for the Competence of Test and Calibration Laboratories in accordance with DIN EN ISO/IEC 17025:2005. In addition to the documented and ongoing controls on workflows already laid out in certification to DIN EN ISO 9001 ff, the accrediting bodies also test the fundamental accuracy of the results of tests and calibrations. Under (EU) Regulation 765/2008, only a single national accreditation body has been nominated since 1/1/2010. In Germany this is the German Accreditation Body (DAkkS: Deutsche Akkreditierungsstelle). Westfalen AG has been accredited via DAkkS. With this accreditation as a test and calibration laboratory, the Westfalen Speciality Gases Centre has provided evidence of its competence at both the national and international level. Precisely defined reference values ensure comparability A standard method for the production of gas mixtures is gravimetry. In other words: the individual components of the mixtures are weighed out. The weights used for this The Westfalen Specialty Gases Centre in Hörstel (near Osnabrück) are regularly checked and certified by authorised weights and measures offices this was another element validated during the accreditation of the Westfalen Speciality Gases Centre. The manufacturing process in individual countries is governed by the primary standards defined and prepared by the various metrology institutes (for example: PTB/BAM, NPL, NIST, KRISS, VSL). Only the successful comparison of so-called secondary standards with the current primary standard allows the user to align to internationally accepted measures. In this way comparability, traceability and reproducibility are assured. Consistent quality for high-grade gas mixtures The accreditation demonstrates our conformance to national and international standards, giving the proof of quality required by DIN EN ISO/IEC /15

3 Achieving accreditation required validation of the measurement methods in use. Validation of the analytical systems at the Speciality Gases Centre in Hörstel The objective of a validation process is to achieve reliable and reproducible results through the suitability of an analysis technique. In other words, the proof and documentation of the reliability of a method. Validation is a quality assurance tool. The validation and the resulting statistical evaluation determine whether the method can be applied. Validation of the methods is a precondition for accreditation. In detail, the accreditations cover the following Accreditation as a calibration laboratory (DKD) The accreditation of the Speciality Gases Centre as a calibration laboratory covers various areas (see table 2). The test result is stated in the DKD calibration certificate. In addition to the results of the measurements and the associated uncertainties of measurement, this certificate sets out the calibration procedures used, the measurement conditions and the reference standard. The calibration certificate documents traceability to the national standards. DKD calibration certificates are recognised worldwide in numerous countries whose accrediting institutes have signed up to the multilateral agreement of the European Co-operation for Accreditation (EA) and the International Laboratory Accreditation Cooperation (ILAC). Accreditation as a test laboratory The Speciality Gases Centre analyses the compositions of gas mixtures, i.e the proportions of certain components in the mixture, in accordance with specified procedures (see table 1). The customer receives a certificate setting out the result in accordance with the requirements of DIN EN ISO/IEC 17025: In addition to the measured values and analytical tolerances, this certificate also indicates the test method used. The Westfalen accreditation certificate. Table 1* Components to be tested NO X CO, CO 2, SO 2, other sulphurous gases CO, CO 2, O 2, H 2, propane, methane, ethane, n-butane, isobutane, hexane O 2 H 2 O n-butanol, N 2 O, acetone Test procedures Chemiluminescence IR and UV spectroscopy Gas chromatography Paramagnetism, electrochemical measurement cell P 2 O 5 cell, dew point mirror hygrometer IR spectroscopy * Overview of test procedures for gases and gas mixtures in accordance with test laboratory accreditation. 1.0/15 3

4 Test gases in accordance with DKD accreditation as a calibration laboratory. Table 2 Measurement quantities/ Calibration item Measurement range/span in 10-2 mol/mol Binary and ternary gas mixtures Mole fraction of carbon to 20 monoxide*) Measurement conditions/procedure Nitrogen or Nitrogen/oxygen mixture* as matrix Lowest assignable measurement uncertainty 1) Carbon dioxide to 100 Propane*) to 1 Nitrogen dioxide to % Sulphur dioxide to 1 1-butanol to % 1-butanol to % Methane*) to 10 Ethane*) 0.01 to 10 n-hexane *) 0.01 to 0.1 n-butane *) 0.01 to 1.5 Isobutane *) 0.01 to 1.5 Hydrogen *) 0.05 to 50 Nitrogen monoxide to 1 Nitrogen as matrix Oxygen 0.05 to 100 Remarks The uncertainties are valid for the specified mole fractions in a mixture of a component and the specified matrix gas. * only outside the ex-zone Dinitrogen monoxide (N 2 O) to % Acetone 0.01 to % Multi-component gas mixtures with reactive gases (each combination is permitted provided there are no safety issues) Mole fractions of to 1 The uncertainties are propane *) Nitrogen or valid for the specified Carbon monoxide *) to 20 Nitrogen/oxygen mole fractions in a Carbon dioxide to 100 mixture*) as matrix mixture of a component and the specified Sulphur dioxide to 1 matrix gas. Nitrogen monoxide to 1 Nitrogen as matrix * only outside the ex-zone Oxygen *) 0.05 to 100 Multi-component gas mixtures with hydrocarbons (each combination is permitted provided there are no safety issues) Mole fractions of carbon monoxide *) to 20 Carbon dioxide Propane *) Methane *) Ethane *) to to to to 10 Nitrogen or Nitrogen/oxygen mixture *) as matrix or methane as matrix n-butane *) 0.01 to 1.5 Isobutane *) 0.01 to 1.5 The uncertainties are valid for the specified mole fractions in a mixture of multiple components and the matrix gas. * only outside the ex-zone 1) The lowest assignable uncertainties of measurement were established in accordance with DAkkS-DKD-3 (EA-4/02). These are expanded uncertainties of measurement with a coverage probability of 95% and have, unless otherwise stated, a coverage factor of k=2. Uncertainties of measurement without a specified unit are relative values relating to the measurement value, unless otherwise stated. 4

5 Measurement quantities/ Calibration item Synthetic natural gas mixtures with mole fractions of the following components Measurement range/ span in 10 2 mol/mol Types in accordance with PTB-A 7.63: May H - 6L -11M -11D -16M -17K Measurement conditions/ procedure Methane as matrix Helium 2 % Oxygen 2 % Nitrogen 0.8 % Carbon monoxide 2 % Carbon dioxide Hydrogen 2 % Ethane Ethene 2 % Propane Propene 2 % Butane 1.5 % Isobutane Pentane 2 % Isopentane 2 % Neopentane 2 % n-hexane 2 % Lowest assignable measurement uncertainty 1) Remarks 1) The lowest assignable measurement uncertainties were established in accordance with DAkkS-DKD-3 (EA-4/02). These are expanded uncertainties of measurement with a coverage probability of 95% and have, unless otherwise stated, a coverage factor of k=2. Uncertainties of measurement without a specified unit are relative values relating to the measurement value, unless otherwise stated. abbreviations used: DAkkS-DKD-3 Expression of Measurement Uncertainty in Calibration, Braunschweig, 1. New edition 2010, Deutsche Akkreditierungsstelle GmbH DIN Deutsches Institut für Normung e.v. EN European standard IEC International Electrotechnical Commission ISO International Organization for Standardization 5

6 Gases I Energy supply I Service stations Westfalen Austria GmbH Aumühlweg 21/Top Leobersdorf Austria Tel Fax info@westfalen.at Westfalen BVBA-SPRL Watermolenstraat Aalst/Alost Belgium Tel Fax info@westfalen.be Westfalen Gas s.r.o. Masarykova Domažlice Czech Republic Tel Fax info@westfalen.cz Westfalen France S.A.R.L. Parc dactivités Belle Fontaine Rosselange France Tel Fax info@westfalen-france.fr Westfalen Gas Schweiz GmbH Sisslerstr. 11/P.O. Box 5074 Eiken AG Switzerland Tel Fax info@westfalen-gas.ch Westfalen Gassen Nederland BV Postbus AT Deventer The Netherlands Tel Fax info@westfalengassen.nl Westfalen AG Industrieweg Münster Germany Tel Fax info@westfalen.com Westfalen Medical BV Rigastraat EW Deventer The Netherlands Tel Fax info@westfalenmedical.nl A T E PSG-G-4.1/11-GB