Gas Standards for Calibrating Vehicle Emission Monitors
Standard gas mixtures are an accurate and cost-effective method for calibrating vehicle exhaust monitors. They are stable and provide a repeatable reference concentration that can be used for regular calibrations.
Each binary standard contains one or more accurately-weighed components mixed with nitrogen or air. Mixtures are available with the following components:
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Vehicle and aircraft emissions |
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| Gaseous Species | Matrix | Amount Fraction Range (mol/mol) |
| Multi-components Carbon monoxide Carbon dioxide Propane Oxygen |
Nitrogen | 0.5×10-2 - 15×10-2 5×10-2 - 15×10-2 500×10-6 - 0.5×10-2 0.5×10-2 - 21×10-2 |
| Carbon monoxide | Nitrogen or Air | Down to 1×10-6 |
| Carbon dioxide | Nitrogen or Air | Down to 1×10-6 |
| Oxygen | Nitrogen | Down to 1×10-6 |
| Propane | Air | 1×10-6 - 5×10-2 |
| Nitric oxide | Nitrogen | 100×10-6 - 5×10-2 |
| Nitrogen dioxide | Air | 100×10-6 - 2×10-2 |
| n-Hexane | Nitrogen | 1×10-6 - 0.1×10-2 |
NPL's gas standards are certified for a period up to three years depending on the stability of the mixture. NPL offers a cost-effective re-certification service after the initial certification period has expired, ensuring temporal consistency of gas traceability.
Contact
Customer Service tel: +44 20 8943 8637
E-mail: gases_enquiries@npl.co.uk
Last Updated: 23 Feb 2011
Created: 27 May 2010