EMISSIONS CONTROL AND VEHICLE INSPECTION

There has been debate since 2015 regarding stricter vehicle inspections. The overwhelming opposition to Low Emission Zones (LEZs) and the lack of alignment between government decisions and the results of five-gas emissions tests – including those carried out by after-sales service centres – prompt us to consider coherent and realistic solutions.

T. Coton, director of Capelec, answers questions from CT Magazine.

CT Magazine: What is your view on developments in emissions testing and the role it has to play in low-emission zones?

Thierry Coton: Over the last 15 years, changes to the Euro emission standards have required manufacturers to reduce exhaust particulate emissions by a factor of five and nitrogen oxide (NOx) emissions by a factor of four. To achieve this, internal combustion engine vehicles have been fitted with emission control systems that have proved to be highly effective; however, like any component, they have a limited lifespan and require maintenance. Consequently, when these systems lose their effectiveness, all the efforts made are undone and the vehicle may pollute just as much as vehicles did 20 years ago.

We cannot, therefore, simply demand that manufacturers achieve ever-lower emission levels through design alone, without also considering the responsibility of the owner to carry out the maintenance and repairs necessary to maintain these low emission levels.

The vehicle inspection is intended to act as the final arbiter on vehicle safety and pollutant emissions, and as far as emissions are concerned, it is urgent that it equips itself with the means to measure fine particulate matter and nitrogen oxides using simple, cost-effective solutions, with standardised, indisputable procedures and limits recognised by all at European level.

Without carrying out these measurements, it is not possible to detect a EURO V/VI vehicle that is polluting more than it should, nor is it possible to play a role in the fairer allocation of Crit’air stickers, which would be based on the vehicle’s actual emissions.

CTM: What is the current state of the art regarding the equipment that would enable these new emissions tests at testing centres?

T.C.: The technologies required to measure fine particulate matter and nitrogen oxides at a technical inspection centre are available and well-established.

The measurement of fine particulate matter in diesel vehicles has already begun in four Member States. This new type of test is covered by European Recommendation (EU) 2023/688, which sets out the specifications for equipment, testing and verification methods, the testing procedure and the limits to be applied. It involves an idling test lasting a few seconds, after which it is clear whether the particulate filter is functioning effectively. This test replaces the opacity test, which is longer and ineffective on EURO V and EURO VI vehicles.

As regards this test on petrol vehicles, the JRC (Joint Research Centre), commissioned by the European Commission, is currently working on a specific procedure. According to the latest reports, an accelerated idling test is yielding promising results.

Finally, regarding the measurement of NOx, the approach would be to carry out a measurement under light load, i.e. at accelerated idling and without a load bank, something we were already advocating in 2016 as part of the French study. The JRC appears to have developed such a method, and it is currently being trialled at several centres, notably in Belgium and Germany.

CTM: What are your thoughts on the proposal put forward by Spheretech?

T.C.: Once monitoring of ultrafine particles and NOx is fully operational at the centres, car repair shops will need to be able to identify the causes and repair the vehicle.

It is in this context that the Spheretech tool, combined with the ‘Eco-maintenance’ approach introduced in car repair shops, comes into its own – as a tool to aid fault-finding and as part of an initiative that supports the development of car repair shops’ expertise in engine emission control.

CTM: So, on the subject of Low Emission Zones, what role could vehicle inspection play?

T.C.: Vehicle inspection centres, once again, if equipped with measuring equipment for NOx and ultrafine particles, could issue Crit’Air stickers based on a vehicle’s actual emissions.

For example, whilst a Euro V/VI vehicle that exceeds emission limits would normally be required to undergo a re-inspection, we could consider, to improve social acceptability, not requiring the vehicle to be brought up to standard but rather downgrading its Crit’air classification, thereby allowing the owner to choose between incurring the costs of bringing it up to standard and forgoing access to Low Emission Zones. It could also allow Euro V/VI diesel vehicles that emit no more than a petrol car to avoid being excluded from urban areas, as is currently planned in the long term.

However, if the aim of the Crit’air stickers is to ban vehicles that emit too much particulate matter from these zones, it seems difficult to justify ‘saving’ Euro III/V vehicles simply through an emissions test. For these categories, a retrofit (electrification or the addition of a particulate filter) must, in my view, be considered and, here again, vehicle inspection could play a role in validating the effectiveness of the upgrade.

Interview by Frank Ferré

Extract from the article ‘Emissions reduction and vehicle inspection’ – CT MAGAZINE - June and July 2023