National Physical Laboratory

Gas standards for vehicle emission measurements

Gas standards for vehicle emission measurements

National and European legislation, such as vehicle emissions regulations, dictates that emission gases are routinely measured to exacting standards. In order to achieve this, it is necessary to utilise accurate and traceable gas standards. These standards can also be used for petrol, diesel and gas turbine engine research, as well as a wide range of development and certification work.

NPL provides gas standards for calibrating vehicle emissions monitors, which can be prepared to the requirements of the customer. The table below gives an indication of the available mixtures; others may be available on request.

Component Matrix gas Amount fraction range
From To
Carbon monoxide Nitrogen 5 mmol/mol 150 mmol/mol
Carbon dioxide 50 mmol/mol 150 mmol/mol
Propane 500 μmol/mol 5 mmol/mol
Oxygen 5 mmol/mol 210 mmol/mol
Carbon monoxide Nitrogen or air 1 μmol/mol 50 mmol/mol
Carbon dioxide Nitrogen or air 1 μmol/mol 50 mmol/mol
Oxygen Nitrogen 1 μmol/mol 50 mmol/mol
Propane Air 1 μmol/mol 50 mmol/mol
Nitrogen monoxide Nitrogen 1 μmol/mol 10 mmol/mol
Nitrogen dioxide Air 1 μmol/mol 5 mmol/mol
n-hexane Nitrogen 1 μmol/mol 1 mmol/mol


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Last Updated: 16 Jun 2016
Created: 24 Sep 2013


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