As part of the Mayor’s campaign against poor inner-city air quality, a new rule has come into effect as of 1 January 2012 that puts a 15-year age limit on London’s infamous black cabs. The measure is expected to affect around 2,600 vehicles as their licence plates expire in 2012.

A report from the Mayor’s office says that the main culprit to airborne pollution rests on road traffic, which contributes to about 80 percent of CO2 emissions in Central London, with the black taxis making up 20 percent of the figure.

New taxi drivers are subjected to a mandatory eco-driving course that teaches them how to reduce costs and emissions through efficient driving. In addition, two full MOT tests are to replace the annual check on the cars, while licences on private hire automobiles are under a 10-year age restriction.

“Delivering cleaner air is key to my goal of creating a better quality of life for Londoners,” Mayor Boris Johnson said in a statement. “I want people to experience a cleaner, greener city before, during and after the Olympic Games.”

Changes are also applied to the Low Emission Zone (LEZ), which lead to new charges for old and polluting vehicles driving in and around London.

“The existing Low Emission Zone is delivering significant improvements in air quality to the benefit of Londoner’s health,” said TfL Interim Director of Congestion Charging and Traffic Enforcement, Nick Fairholme. “The vast majority of owners and organisations have taken steps to prepare. Transport for London has a team of people in place to provide practical advice to anyone who remains concerned about how these new standards will impact them.”

TfL and the Mayor’s office also announced a £1mln fund made available to encourage drivers to move over to low emission electric vehicles in a bid to further tackle the issue of air pollution.