AIR Index FAQs

Frequently asked questions

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  • In the wake of the Dieselgate scandal, levels of public and political trust in regulated automotive testing dropped to an all-time low. Most of the processes used to measure vehicle emissions became discredited, creating an information vacuum.
  • Low levels of understanding and the lack of reliable and genuinely independent information fuelled a public policy debate that was seldom founded on factual and credible evidence.
  • The global policy response was fragmented and did not yield immediate results and could even negatively impact personal mobility, air quality and greenhouse gas emissions.
  • In some cases, policy decisions may actually be exacerbating the problem as the following two examples illustrate:
    • Systems in place in some major cities which use the Euro standard as the basis for vehicle ratings are penalising older cars, some of which have lower NOx emissions than newer models
    • Banning diesel vehicles without discriminating between ‘cleaner’ and ‘dirtier’ to address NOx concerns, may actually result in an increase in the levels of CO2 as consumers revert to petrol vehicles in the absence of battery or hybrid vehicles that meet consumer needs. This has happened in Europe already.
  • In the absence of one international rating system, different policies between countries, regions and even cities have arisen, based on inconsistent data, leading to consumer confusion and industry uncertainty.
  • A harmonised, accurate rating system was needed.

The AIR Alliance provides an independent, harmonised and accurate rating system called the AIR Index and make it freely available to enable the immediate improvement in air quality from vehicle emissions.

Everyone can use the AIR Index and improve the air that we breathe:

Governments, cities, academics, NGOs and other organisations committed to improving air quality and reducing greenhouse gas emissions can join the AIR alliance to help drive the voluntary global adoption of the AIR Index.

Car makers can adopt, voluntarily the AIR Index and follow the same approach to car emissions as they use with NCAP for car safety.

Policy makers can adopt, voluntarily the AIR Index as the basis for informed, fair and effective air quality policy decisions.

Like-minded organisations aligned to the principles of the AIR Alliance can provide funding to help secure the long-term independence of the test results, the test methodology and their global application.

The AIR Alliance is making past and future results from independent testing of vehicle emissions freely available through the AIR Index to everyone so they can make informed choices. The comparable and credible test results in the AIR Index:

  • Enable car buyers, whether consumers or fleet managers to make the right choices in the cars they buy – new and used.
  • Empower policy makers and regulators to develop robust, fair and effective policies to help them improve air quality in the short and long term for the health of their communities.
  • Enable car makers to regain consumer trust by competing effectively to deliver cleaner cars with independent verification of their achievements.

AIR has enabled the development of the test methodology CWA 17379 and invites third party testing providers, with the opportunity to accredit them to conduct similar tests to the same standards around the world.

The AIR Alliance is a global not-for-profit organisation whose members and supporters enable the AIR Index to be made freely available for car buyers and policy makers.

The AIR Alliance was formed in 2017 by Nick Molden, founder of Emissions Analytics and Massimo Fedeli of Fair Play Consulting and is an alliance of scientists, individuals and organisations including NGOs and philanthropists committed to addressing NOx and CO2 emissions from vehicles.

Supporters are the individuals who align with the aims and ambitions of the AIR alliance, follow our news and events, make informed decisions on vehicle choices and extend the reach and influence of our communications to accelerate the improvement in urban air quality.

Members of the AIR Alliance enable the development and adoption of policy. They are listed on the home page of the AIR website and currently include:

  • Air Srl
  • The Bruno Kessler Foundation
  • CENEX
  • The Energy Savings Trust
  • MotorCheck
  • Sanity System

Members of AIR contribute in a number of ways to ensure the independence and scientific integrity of the AIR Index including accreditation of the testing protocol and rating, vehicle testing and the policy makers, car buyers and users of the AIR Index.

The AIR Alliance is a global not-for-profit organisation whose members and supporters founded the organisation to develop and produce the AIR Index as a freely available resource to help car buyers and policy makers improve air quality.

The AIR Alliance receives fees from organisations requesting emission tests to be carried out on vehicles to be included in the AIR Index.

The AIR Alliance commissions and pays for vehicle tests from the pool of accredited, independent test centres using vehicles sourced independently from car makers.

The AIR Alliance funds research and communication to promote the adoption of clean vehicle technology to improve air quality in towns and cities worldwide.

The AIR Index is a global first. It is the only system that aims to provide standardised data consistently across the globe. It will help reduce emissions more effectively while minimising the impact on individual mobility by using the most comprehensive and comparative data available now.

The data from AIR Index can be used to make an immediate and meaningful difference to urban air quality and reduce to greenhouse gas emissions. It is:

COMPARABLE: It is based on the most thorough assessment of on-road driving conditions using the CWA 17379 and CWA 17934 methodologies, enabling genuine comparability between vehicle models and makes, both new and old.

ACCESSIBLE: Data are publicly available, transparent and free of charge.

STANDARDISED: Based on the European CEN methodologies CWA 17379 and CWA 17934 to deliver a data set across all markets and regions providing a truly global rating system for tailpipe emissions and vehicle interior air quality (VIAQ).

INDEPENDENT: It is the most comprehensive, independently endorsed, data available in the market place.

IMMEDIATE: The data is available now, today.

The AIR Alliance has invited a Scientific Advisory Committee (SAC) comprising 9 leading international academics in the fields of emissions and air quality to scrutinise the AIR Index. The testing conforms to the latest European CEN methodology and is sufficiently robust for car makers and policy makers to take immediate action to solve the NOx crisis and address exposure to pollutants inside the vehicle.

RDE is a significant achievement but it is not enough. It’s a first step in addressing Europe’s NOx crisis and longer-term emissions problems, but it will not provide an immediate solution

The European Commission has acted to strengthen RDE by creating a framework for independent surveillance of testing by third parties, and while more stringent than laboratory tests, the RDE:

  • Is not independent as the tests will still be performed directly or indirectly by manufacturers
  • Will not be fully standardised as each manufacturer can test to different cycles.
  • Only applies to new models introduced to the market after 1 September 2017. Testing for all new vehicles was only introduced during 2019, leaving a fleet of vehicles caught between the two.
  • The AIR Alliance follows strict corporate governance rules and guarantees that the data and testing remain completely independent from both car makers and regulators to ensure trusted disclosure and public scrutiny.
  • The AIR Alliance has developed funding through its members and supporters which maintains the independence of testing and data from car makers and regulators to retain the AIR Alliance’s vision and clarity of purpose.
  • The success of NCAP’s independent and voluntary approach is a tried and tested model to apply to the challenge of addressing car emissions.
  • By adopting the the AIR Alliance approach, car makers can make a difference now and demonstrate their commitment to regaining the trust of consumers and policy makers.
  • Policy makers can choose to use the data to make immediate changes to current policy and improve those policies as the data grows from further testing.
  • A voluntary approach takes politics out of the issue and focuses instead on driving a solution to a global problem.
  • Following the NCAP experience, the AIR Index provides a similar framework for car and van makers to achieve competitive advantage by reducing harmful NOx emissions.
  • Innovation is incentivised, with car and van makers attracting customers and increasing market share by creating ever cleaner models and showing how they will improve the existing fleet. The results, as seen previously with safety, are likely to far exceed current expectations and be achieved in the shortest possible time.
  • The AIR Alliance offers the most comprehensive approach to rebuilding consumer confidence through its independence, scientific rigor and transparent rating of emissions in the AIR Index from A-to-E.
  • Today, the residual value of diesel vehicles in the short term – and petrol vehicles in the longer term – will come under further pressure if consumers remain confused by the conflicting stories around on-road emissions and stop buying vehicles. This will have a negative financial impact on car and van makers, fleet and leasing companies, as well as private owners and the AIR Index provides a practical, trusted and clear way of presenting the facts for car and van buyers and policy makers.
  • Understanding CO2 alongside NOx emissions could help avoid a market switch to higher CO2 emitting vehicles, which would make it harder for car and van makers to meet their fleet CO2 targets.