Counting to be included in exhaust gas testing: Particle counting for diesel vehicles from 1/1/2023

13. Mar 2022 | Industry + More

The automotive industry has been working on this topic for many years: Particle counting for diesel vehicles. The back and forth will come to an end on 1 January 2023.

We are all aware that nothing came of the particle counting as part of exhaust gas testing announced for Euro diesel vehicles in 2021. At that time, there simply wasn't the necessary device specifications and specific specifications for the counting process. At the time, the plan was to delay the launch by at least two years.

Particle counting as part of exhaust gas testing from 1/1/2023

Now the back and forth has come to an end. It has been clear since 2021 that particle counting is coming. This is indicated in the exhaust gas testing directive, which was published in Verkehrsblatt number 8/2021 in April 2021.

The Verkehrsblatt publication stipulates that all Euro 6 vehicles with compression ignition engines must be subjected to particle counting as part of the exhaust gas testing as of 1 January 2023. The new testing procedure is to be integrated into the existing exhaust gas testing process.

"The introduction of a new counting method was necessary because vehicles with a compression ignition engine and emissions regulations Euro 6/VI and better have a particulate filter", reported autoservicepraxis.de. The conventional turbidity measurement is no longer sufficient for checking exactly how effective a particulate filter actually is.

The opacimeter isn't completely obsolete, however. After all, the emissions of Euro 5 models and lower will still be tested using the turbidity metre.

Investments in the 5,000 to 10,000 euro range required

In an interview with "asp", Thomas Sieber, Technical Director of the monitoring organisation at TÜV SÜD Auto Service, explains: "The conditioning is similar to the turbidity measurement; however, the actual measurement (particle counting) takes place when idling. For the measurement itself, acceleration to maximum rated speed is therefore no longer necessary."

For automotive companies who want to continue to test vehicles with compression ignition engines and Euro 6/VI emission class and higher, this means buying new equipment once again. According to Sieber, investments in the 5,000 to 10,000 euro range are required.

Particle counting: CPC method vs. DC method

According to "Krafthand", two counting methods have emerged: CPC technology (Condensation Particle Counter) and DC technology (Diffusion Charger) meet the defined specifications for particle counters. In an interview with the trade magazine, Dekra expert Thomas Obst explained that the CPC method offers a higher counting accuracy, while the DC method has advantages in terms of costs.

According to Dekra, the particle counting process includes a total of six phases. All particles above a size of 23 nanometres are measured, with a maximum limit of 250,000 particles per cubic centimetre. Important: This limit applies to all diesel vehicles from Euro 6 - and therefore also for trucks and buses. 

Experts expect many workshops to wait before purchasing a particle counter, however. TÜV, Dekra, GTÜ and KÜS will carry out most measurements for the foreseeable future...