Particulate Number (PN) testing could be added to the yearly MOT as the government looks at ways of improving emissions testing for diesel cars.
The Driver and Vehicle Standards Agency (DVSA) is trialling the tests with 10 garages across the UK to decide “whether it is practical to bring this into the MOT”.
These garages are also using varying PN tester types to see what may be most suitable if the pilot is a success.
The difference between current testing, which measures the density of the smoke emitted from the vehicle, and PN is that it doesn’t measure the size or quantity of the particles within that smoke – and it is these smaller particles that “are very harmful to us and therefore measuring them will bring both air quality and health benefits”, the DVSA’s head of MOT policy, Chris Price, said.
Research conducted by the Department for Transport (DfT) into the use of PN testing equipment for the MOT also concluded that it provided an effective means of identifying removed or damaged DPFs (diesel particulate filters), with significant advantages over current testing methods.
Some countries across Europe already use PN testing during their MOT test, and “we’re looking into whether it would be feasible to do that in GB”, Price said.
He added that “we know garages may have to invest in this equipment” if the testing is brought in, but said “we want to reassure you that we won’t be making these changes without thorough consideration – and we do understand that uncertainty about dates of first MOT (for example) can affect those investment decisions a garage may make.”
But, he backed the pilot, concluding: “It’s important we do what we can to keep everyone safe by improving air quality – and that maximising the value we get from the MOT helps secure its future.
“We understand that no matter what happens with the potential MOT modernisation, it will need careful and considerate change management. This will ensure that industry and other stakeholders are properly engaged and involved in future decisions.
“DfT are therefore establishing a stakeholder review group that industry trade groups will be involved in to help guide this work if needed. We hope this will be a good way for the ‘voice’ to be heard in future changes.”