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The AIR Index – The Testing Process Infographic
Whether they are diesel, petrol, hybrid or electric, the most accurate way to measure harmful emissions is to test cars on the road in actual driving conditions.
Every car with a published AIR Index rating is tested in accordance with the CWA 17379 methodology ensuring a series of strictly controlled, independently conducted tests using Portable Emissions Measurement Systems (PEMS) equipment.
This infographic shows some of the detailed parameters when testing vehicles for rating in the AIR Index.
Would you donate £10 to support the work of the AIR Alliance?
We provide practical solutions, including the AIR Index vehicle ratings, to ensure that independent, scientifically robust data are available to inform discussions and policy decisions which can help reduce the impact of harmful vehicle emissions. We are guided by a committee of the world's leading emissions and air quality experts who give their time and expertise to support our common goal of improving air quality and tackling the climate crisis. The AIR Index ratings and our expertise are used by public authorities and organisations across Europe to inform policy decisions. The AIR Alliance is a not-for-profit organisation and we fund our own testing and scientific programmes to provide AIR Index ratings free of charge. Please would you consider making a donation to support our work?
A small donation can make a big difference and takes moments to send. If you can. please consider supporting us with a regular amount each month.