The company, which gathers real-world vehicle emissions data using a portable measuring system, supplied some of the information used for the 2014 report which led to the Environmental Protection Agency (EPA) and California Air Resources board carrying out further tests on Volkswagen’s diesel engines.

It says it has tested over 1,000 vehicles in the U.S. and Europe, aimed at helping to change the test regime and rebuild trust between car manufacturers and consumers. During on-road testing, it says that NOx emissions are four times above the laboratory limits, while CO2 emissions are one third over official figures.

Emissions Analytics is now seeking partners to launch an independent accreditation initiative which will provide the data it gathers to consumers as an additional measure of performance.