Accredited Gas Mixtures
A Comprehensive Range of Gases in Accordance to ISO17025
It is a requirement of both ISO 17025, and MCERTS accreditations that calibration gases used for the quantification of emissions are traceable. It means that there is an auditable chain of direct measurements linking the value of the calibration gas back to primary standard gas mixtures and ultimately to the SI units.
Understanding the legislative demands, Air Liquide has the solution, by offering a comprehensive range of calibration gases that are certified in accordance to ISO17025 in our calibration laboratory in Gellep. The traceability, accuracy and stability of our gas mixtures ensure that the user has a quality product fit for purpose.
ISO17025 DKD Calibration Gases - Emission Control
| Conversion Factors (0ºC and 101.kPa) ppm / mg Nm3 | |||||||||
| NO | NO2 | SO2 | CH4 | CO | CO2 | NH3 | HCl | HF | |
| 1.340 | 2.054 | 2.860 | 0.716 | 1.250 | 1.965 | 0.760 | 1.628 | 0.893 | |
| Binary Gas Mixtures | ||||
Gas |
Matrix |
Concentration Range |
Relative
Uncertainty |
|
Carbon Monoxide |
Nitrogen or Air |
10ppm – 20% |
+/-1% |
|
Carbon Dioxide |
Nitrogen or Air |
10ppm – 20% |
+/-1% |
|
Methane |
Nitrogen or Air |
1ppm – 100ppm |
+/-1% (<10ppm +/-2%) |
|
Propane |
Nitrogen or Air |
1ppm – 1% |
+/-1% |
|
Sulphur Dioxide |
Nitrogen |
20 – 5000ppm |
+/-1% |
|
Nitrogen Dioxide |
Nitrogen |
3 - 1000ppm |
+/-1% (<10ppm +/-2%) |
|
Nitric Oxide |
Nitrogen |
1 – 4500ppm |
+/-1% (<100ppm +/-2%) |
|
Oxygen |
Nitrogen |
1 – 25% |
+/-1% |
|
| Quaternary Gas Mixtures | ||||
Gas |
Matrix |
Concentration Range |
Relative
Uncertainty |
|
Carbon Monoxide Carbon Dioxide Propane |
Nitrogen |
0.2 – 5% 1.5 – 18% 150 – 1000ppm |
+/-1% +/-1% +/-2% |
|
Carbon Monoxide Carbon Dioxide Propane |
Nitrogen |
0.2 – 5% 1.5 – 18% 1000 – 5000ppm |
+/-1% +/-1% +/-1% |
|
Download DKD Scope of Accreditiation Certificate...
International Recognition & European Co-operation
In the course of proceeding globalisation and a coalescing Europe the mutual recognition of national calibration certificates is essential.
In Europe this is done by multilateral agreements (MLA) within the European co-operation for Accreditation (EA), which in the meantime almost all European accreditation bodies for calibration and testing laboratories as well as certification bodies belong to.
Mutual recognition is based on:
- A harmonisation of the accreditation criteria and procedures
- EA interlaboratory comparisons
- evaluations of the accreditation bodies by international peer teams
The European standards for accreditation bodies of calibration and testing laboratories as well as their assessment and evaluation provide the basis for this.
Worldwide the national accreditation bodies have syndicated in the International Laboratory Accreditation Cooperation (ILAC), whose main objective is the creation of a network of agreements for the mutual recognition of calibration certificates and test reports of accredited laboratories.
This network is to improve above all the acceptance of these certificates and reports by member states of the World Trade Organization (WTO) within the scope of the agreement on the removal of technical barriers to trade (TBT Agreement) of 1995. ILAC thus supports the work of the respective regional organizations, e. g. EA and APLAC (Asia Pacific Laboratory Accreditation Co-operation). DKD is a member of ILAC and belongs to the signatories of the "ILAC Mutual Recognition Arrangement" for the mutual recognition of calibration certificates and test reports (further details see EA or ILAC).
 |
Austria BMWA |
 | Belgium BKO/OBE |
 | Denmark DANAK |
 | France COFRAC |
 | Germany DKD |
 | Greece ESYD |
 | Italy SIT |
 | Netherlands RVA |
 | Portugal IPQ |
 | Spain ENAC |
 | Sweden SWEDAC |
 | Switzerland SAS |
 | UK UKAS |
Contact Us
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