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London ULEZ: Euro 6 ‘wrong standard’ for diesel access

ultra-low emisson zone sign in London

Allow Independent Road-testing (AlR) welcomes the launch of the Ultra Low Emission Zone (ULEZ) in London on Monday (April 8), but has again claimed it will not stop ‘dirty diesels’ from entering the capital.

Under the ULEZ scheme, penalty-free access to the centre of London will only be granted to petrol cars with a minimum Euro 4 standard while diesels must comply with the Euro 6 standard. Non-compliant cars must pay £12.50 to enter the ULEZ on top of the Congestion Charge.

However, AIR says tests it has conducted, rated in the AIR Index, show that many Euro 6 diesels will legitimately still be producing many times the officially published NOx limit, with free access to ULEZ.

When a 2017 Renault Clio 1.5 litre dCi diesel was tested and rated in the AIR Index, it emerged that the supermini emitted 20 times more NOx in urban driving than a 2018 Land Rover Discovery 3.0 litre TD6 diesel, yet both fall under the category of ‘Euro 6’. What’s more, some Euro 6 diesels produce more urban NOx than earlier, cleaner Euro 5 vehicles, says AIR.

The results of variations between Euro 6 vehicles was presented at the launch of the AIR Index in February 2019.

AIR Index co-founder Nick Molden said: “Whilst the latest phase of the Euro 6 standard – in this case 6d which includes on-road testing - does set low levels of urban NOx emissions, millions of cars with a pre-Euro 6d standard have been sold across Europe and some are still on sale today. All these have unlimited ULEZ access since they fall within the overall Euro 6 stage.

“The fundamental issue we have with ULEZ access being based upon Euro standards alone, is that is not an efficient or fair way to address the problem of urban NOx emissions from vehicles, since over-emitting newer Euro 6 cars will be allowed in, yet older lower-emitting Euro 5 cars will attract penalty fines.”

The AIR Index rates vehicles tested in urban conditions to the same standardised methodology providing comparable NOx emissions levels that more accurately reflect the contribution to urban air quality than existing tests performed in a laboratory.

AIR says it has been created to “inform and empower” car buyers and policy-makers about vehicle emissions when making choices about car purchase and usage.

An A-E colour-coded rating, shows the difference between clean and dirty vehicles based on how much NOx comes out of a car’s tailpipe in urban driving.

“We believe that ULEZ should be based on a better source of data,” continued Massimo Fedeli, operations director and co-founder of the AIR Index.

“Without a better source, the positive benefits will be seen more slowly, and the number of car-owners affected will be greater than necessary.

“It would immediately be more effective if used in conjunction with the ratings provided through the AIR Index. This would enable access to only the cleanest vehicles and limit the over-emitting vehicles from adding further to poor urban air quality.

“Specifically, a C-rated Euro 5 diesel could be let in, but an E-rated Euro 6 should not be.”

At the launch of London’s ULEZ, AIR is calling on policy-makers across Europe to look at the most effective way to use actual vehicle emissions, not just laboratory standards, as the basis for policies which will bring cleaner air, more quickly to everyone.

“Even at the most optimistic predictions, the current rate of adoption of zero emission vehicles is not happening quickly enough to help us, our friends and families, colleagues and citizens who need immediate respite from urban air pollution,” said Fedeli.

“To make rapid progress, we need to make best use of the cleanest internal combustion engine technology available today and deliver a real improvement in air quality immediately. There can be no excuse for failing to use the most effective ways available to us now, to improve urban air quality for everyone.”

Further information about Allow Independent Road-testing (AIR) can be found at www.allowair.org.

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  • Peter - 05/04/2019 11:46

    While the AIR index may indeed highlight the inconsistencies within Euro 5 and Euro 6 vehicle categories, it is a long way from being comprehensive enough to be the basis for a charging regime. I thought I would look up my vehicle, being a Xmas 2014 reg. however the only variant in the database is a Euro 3, 2005 model. In the absence of a viable alternative, how are cities supposed to draw the line?

  • Rudolf Huber - 05/04/2019 18:56

    Does this mean that we finally get real world emissions tests that really deserve the name? If yes, I predict hard times for anything that's not ultra clean in many cities as this would inevitably be copied elsewhere. The only way to use a heavy truck in a city center will then be either LNG or E-Vehicles knowing well that the electric option will carry a hefty price tag.

  • Andrew Mackintosh - 30/04/2019 04:41

    The Euro standard is being used because people are most familiar with it. Most people who own a diesel will have some idea of the standard their vehicle complies with by looking at its age. Any other rating standard would require retesting every single car on the road for compliance, and then relaying that information to the public. The average person simply isn't going to understand why their 2016 Renault Clio has to pay more than a 2009 Vauxhall Zafira.

  • SRH - 15/06/2019 18:37

    Every vehicle over three years old has to have an MOT test, the emissions are tested at every MOT test, every year, twice a year for PCO private hire vehicles. There has alway been an easy way of checking the emissions of every vehicle over three years old, but of course TFL would lose a fortune in revenue and will also be shown up as the ill advised, unless money grabbing body that they have always been. Charging a fee for non compliant vehicles does not help clean the air in London, it just makes money for TFL, which let’s face it, is all that they are interested in! I have vehicles that are according to TFL are now Euro 3 within the ULEZ, Euro 4 within the M25, but are now classed as Euro 5 in the rest of Europe as the actual emissions are so low! I have recently had one 2004 vehicle checked and the ppm was 0.000 and that was without its £4500.00 DPF fitted at the time of the test. When this new ULEZ goes live, there will be between 80,000 and 90,000 extra people out of work, who will pay for their benefits? They will be out of work due to not being able use the vehicles that they currently drive and like myself, cannot afford to spend £55,000.00 on a replacement to drive.

  • Anthony - 30/12/2019 18:15

    Illogical. We can only buy the vehicles we are offered, and abide by the regulations that exist. if the Euro 6 standard is now not sufficient, then this constitutes a fraud on the people who bought them.

  • Agostino Mascio - 16/06/2020 19:48

    Hi can you tell me if I purchase a euro 6 Mercedes Diesel 2016 this year will the government change the goal post again and say it needs to be a euro 7 next year or in two year time as i understand it the older the car the more Emission that pollutes

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