The French carmaker PSA/Peugeot-Citroen has developed a new particulate filter with a longer life than those already on the market.

The new equipment, which reduces soot particulates from diesel engines, is designed to last for a vehicle's entire lifetime, rather than around 75,000 miles.

PSA's diesel cars will be fitted with the new filters from early 2004, as part of a programme by the manufacturer to anticipate through research and development new EU anti-pollution laws, which take effect in 2005 and 2008.

European countries tax petroleum intensely to encourage the use of fuel-efficient diesels, with around 42 per cent of new vehicles purchased in Europe in April this year running on diesel engines.

Soot particles in the new filter are burnt in a container close to the fuel tank, using an additive, although some German carmakers prefer to reduce particulates through engine tuning rather than by adding a filter.

Renault SA's catalytic filter, for example, burns soot using a platinum coating on the particulate trap that acts as a catalyst.