The US Environmental Protection Agency (EPA) and American Engine Manufacturers Association (EMA) have agreed on a programme of emissions testing on large diesel trucks.

Portable on-board measurement systems will monitor emissions, with the test programmes being run by the manufacturers themselves. The tests will be the first time that such measurement systems have been used.

The specific regulations for the tests will be announced by the EPA some time during the next twelve months.

The EMA has insisted, though, that the Agency provides guidance documents that will give manufacturers detailed instructions as to how to conduct the tests and what they are supposed to be measuring.

The settlement comes after much wrangling and disagreement between the two organisations as to how environmental considerations should be tackled by the industry.