Major US automotive firm Mack Trucks and its parent company Volvo Trucks North America have announced they will be using diesel particulate filters (DPF) to help meet the standards required by the US 2007 emissions legislation.

The firms confirmed that they would implement DPF in conjunction with the exhaust gas recirculation (EGR) to limit emissions.

Volvo Trucks says it will begin testing the technology in Spring 2005, before rolling it out.

The news follows announcements by a string of truck firms concerning the new legislation, with EGR and DPF technology being supported by Cummins and Navistar, while Caterpillar has opted to use ACERT engines with DPF.

Meanwhile, the Bush administration revealed today that it was pushing ahead with plans to promote hydrogen-based cars.

The President has thrown his weight behind a campaign to drive a 43 per cent increase in federal funds to develop cars that run on hydrogen fuel and the associated infrastructure to support the vehicles.

The extra funding would build on a level of funding that already stands at $228 million for the 2005 spending year, under the White House's proposed government budget announced this week.