De-risk your fleet emissions The effective way to strengthen procurement and control costs

CO2 Band
Fuel Type
AIR Index
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Air Index - Diagram

The AIR Index can help fleet managers reduce the total cost of ownership (TCO) for fleets by choosing the cleanest vehicles to deliver significant long-term benefits.

Most fleets use CO2 data as the primary filter to segment vehicle choice but this doesn’t address the potential additional future operational costs as cities control access based on vehicle emissions.

The AIR Index provides fleet managers with a trusted, transparent and independent rating of vehicles from A-to-E of actual NOx emissions, searchable by CO2 figures, Euro standard and fuel type to inform planning decisions and help to select the cleanest vehicles, minimising the total cost of ownership. Fleet policy can be strengthened by using the A-to-E rating during procurement to match city policies where the vehicles operate.


All cars tested for the AIR Index meet the European emission standards required at the time of delivery, such as Euro 4, 5 or 6. The AIR Index A-to-E rating provides a deeper, more realistic, independent assessment of the actual and relative emissions of each car.

Informed decision making

Upgrade vehicle polices to control and reduce risk

Fleet policies based on data sources such as CO2 and Euro standards don’t provide an accurate measure of on-road vehicle NOx emissions, yet regulation to improve air quality by controlling access to towns and cities on this basis is already in use and being adopted rapidly.

Effective management of car choice by NOx emissions is critical, since access to towns and cities for only the cleanest vehicles will increase operational costs and reduce the residual value of vehicles which fall outside the permitted air quality levels.

The AIR Index provides fleet managers with a reliable, trusted and independent framework to inform fleet policy and control TCO. The scientific results of on-road emissions reveal that some diesel engines actually produce lower NOx emissions than petrol engine variants and the AIR Index provides clarity when developing a robust fleet policy.

Integrate with your systems
Need to integrate your data with the AIR Index?

The AIR Index is a global first. It is the only system that provides comparative emissions ratings based on standardised on-road testing. The AIR Index rating categorises vehicles in bands, based upon NOx emissions data measured during on-road tests. Testing each vehicle in urban conditions to the same test provides comparable NOx emissions levels that more accurately reflect the contribution to urban air quality than simulated tests performed in a laboratory. It also provides full comparability between vehicle makes and models, both new and old.

The data is publicly available, transparent and free of charge. Fleet managers are offered access to the database via API to enable effective decision making to improve air quality.

Contact us for more information and to access the AIR Index.

Join us in the AIR alliance

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