Paris tries something different in the fight against smog

Under a new French scheme cars are labelled according to the pollution that they emit. This allows the worst offenders to be banned when necessary

Last week Paris suffered its fourth smog of the winter and tried a new idea to protect its residents from the worst effects. Like many European cities, the Paris region has a well-established system of emergency actions that escalate if smog persists. Initial steps include health warnings, reduced speed limits and restrictions on lorries in the city centre. Final steps include cheaper public (a3.80 for a day pass), and bans on half of cars, using an odd/even number plate system.

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