Using lasers to test pollution levels

As our towns and city centres become increasingly clogged with traffic the focus has intensified on what exactly is being produced by the cars on our roads, and this has increased still further after the Volkswagen emissions scandal.

The lasers, which are manufactured in the US by Edar, shine a beam through exhaust fumes and use reflected light to measure levels of toxins and analyse levels of pollution. The technology has been pioneered by former NASA scientist Stewart Hager who had been working on a US-based project that used lasers to measure the abundance of CO2 in the atmosphere and realised the same principle could be used to measure car emissions.

Although the system can identify individual vehicles, for the purpose of the trial the data is anonymous. However, it will be able to identify car emissions on a vehicle by vehicle basis under real world driving conditions.

Measuring exhaust emissions is part of a car’s MOT test. However, the car review website www.honestjohn.co.uk has calculated that many cars use more fuel and less miles per gallon than the manufacturers claim – and of course, more fuel burned equates to increased carbon dioxide emissions. The website also stressed that the way cars are assessed in laboratories often don’t reflect real world driving conditions and as such, have welcomed a new testing process.

The government has stated that although the analysis is in its early stages it will help to improve the accuracy of measuring air quality.